Neighborhood History as a Factor Shaping Syringe Distribution Networks Among Drug Users at a U.S. Syringe Exchange

Abstract

Throughout the US, high-visibility drug markets are concentrated in neighborhoods with few economic opportunities, while drug buyers/users are widely dispersed. A study of Pittsburgh Syringe Exchange participants provides data on travel between and network linkages across neighborhoods with different levels of drug activity. There are distinct racial patterns to syringe distribution activity within networks and across neighborhoods. Pittsburgh’s history suggests these patterns emerge from historical patterns of social and economic development. Study data demonstrate the ability of IDUs to form long term social ties across racial and geographic boundaries and use them to reduce the risk of HIV transmission.

Social networks have been a significant area of study in regard to HIV risk and prevention among drug users. Network characteristics that have been found to shape injection risk behavior include size and density (Latkin et al., 1995; Latkin et al., 2004; Friedman et al., 1999) and turnover of membership (Hoffmann et al., 1997). Drug user networks play a significant role in prevention, as well as risk, by extending the reach of syringe exchange programs (SEPs) through “secondary” or “satellite” exchange (Snead et al., 2003; Sears et al., 2001; Valente et al., 1998) and communication about HIV and risk behavior (Latkin et al., 2003; Friedman et al., 2004; Friedman et al., 2005). Significantly, while network ties are generally homophilous among drug users (Kottiri et al., 2002; Pierce, 1999), as in the rest of US society (McPherson et al., 2001), both geographic (Williams et al., 2005) and racial (Kottiri et al., 2002) network “bridging” have been associated with HIV transmission. Certain urban environments may facilitate network bridging by bringing together drug users from diverse social and geographic locations; some low income neighborhoods develop high levels of drug-related activity (Ford and Beveridge, 2004; Saxe et al., 2001) and drug markets draw drug users from outside of the immediate neighborhood (Saxe et al., 2001; Andrade et al., 1999; Bourgois, 1996; Curtis et al., 1995). The centrality of networks to both HIV risk and prevention among drug users, and the existence of locations with concentrated drug activity where network bridging may occur, suggests the importance of developing a deeper understanding of the interactions among networks, neighborhoods, and HIV prevention.

In 2001, a case study of the Prevention Point Pittsburgh (PPP) SEP included a social network component that specifically examined travel between neighborhoods as an element of network activity. At the time of the study, PPP was an unauthorized program, and did not conduct any public exchange sites or operations. Program participants would contact PPP volunteers by phone to pick up syringes, other safe injection supplies, and condoms for themselves and others. Participants could also return syringes for safe disposal, although direct “exchange” of used syringes for clean ones was not required. Two individuals, “Mike” and “Karen” (not their real names) functioned as “core distributors,” taking thousands of syringes from PPP weekly and distributing them to other drug users. This paper uses the social network data from the 2001 case study to examine the syringe distribution networks of IDUs obtaining syringes from PPP, with particular attention to how network activity enabled distribution of syringes across diverse social and geographic spaces within the city of Pittsburgh.

PPP’s outreach strategy constitutes a form of secondary or satellite exchange, in which one IDU obtains syringes from an SEP in order to give the syringes to one or more other IDUs (Snead et al., 2003; Valente et al., 1998). Previous studies of secondary exchange have examined satellite distribution associated with legal SEP, and identified networks as central to secondary exchange (Snead et al., 2003; Sears et al., 2001; Valente et al., 1998). SEP participants who engage in satellite exchange have larger syringe circulation networks than other SEP participants, (Valente et al., 1998) but little else is known about the characteristics of these networks. This study of syringe distribution networks extends previous work on secondary exchange by gathering detailed information on the networks through which syringe distribution takes place, in a context where there was no legal SEP.

This study addresses the inter-connection of social and spatial elements of drug user networks by identifying the neighborhoods that respondents lived in and the neighborhoods in which they interacted with network members. This neighborhood data enables examination of the strategic role of racially and geographically non-homophilous network ties in relation to drug-related activity, including HIV prevention, and how race and neighborhood shaped respondents’ negotiation of selected legal and health risks associated with drug injection.

Questions about the relationship among neighborhoods, social ties, and network homophily are not unique to studies of drug users. Network homophily appears to be normative across a range of social contexts and research studies (McPherson et al., 2001) and networks often have strong geographic boundaries and a distinctive character (Greenbaum and Greenbaum, 1985). Studies of drug user networks can add to these larger questions about homophily and neighborhoods by shedding light on particular social contexts and dynamics that may encourage network bridging. For example, while residents of some neighborhoods experience social stigma related to living in an area known for poverty and illegal activity (Warr, 2005), for someone seeking to obtain drugs or injection supplies an associate’s residence in such a neighborhood could be considered a positive relational attribute due to the potential for direct or indirect connections to local drug scenes.

As already noted, multiple studies have found that certain neighborhoods have high concentrations of drug-related activity and attract drug users from throughout a city (Ford and Beveridge, 2004; Saxe et al., 2001; Andrade et al., 1999; Bourgois, 1996; Curtis et al., 1995). Ford and Beveridge (2004) define these areas as “high visibility drug markets,” characterized by geographically concentrated drug buying and selling that occurs with little or no effort at concealment, and found that these areas are also characterized by a dearth of legitimate commercial establishments such as laundromats, supermarkets, or movie theaters. A study of an area that fits these criteria described a sociometric network structure among drug users in which a “core” group engages in a high level of ongoing activity within the drug market itself and a “periphery” population enters the market only episodically in order to conduct specific transactions (Curtis et al., 1995). Significantly for thinking about homophily and neighborhoods, one of the roles of core members is to facilitate drug transactions by those on the periphery (Curtis et al, 1995). This interaction between core and periphery is in keeping with observational studies of drug-market neighborhoods (Andrade et al., 1999) and white IDU networks (Pierce, 1999) that describe encounters in which drug users from outside a neighborhood rely on “locals” for assistance.

These observed patterns of interaction within drug markets raise the question of how the characteristics of a neighborhood can facilitate the development of ties between persons who live in different parts of a city and/or come from different social groups. The consistent finding that drug users from around a city come to these high-visibility markets suggests that drug market activity needs to be situated within larger ecologies of drug use (Saxe et al., 2001); the distinctive neighborhood characteristics of these areas (Ford and Beveridge, 2004), in turn, suggest that high visibility drug market areas need to be situated within historical patterns of urban development. The relationship between historical processes and contemporary social interaction and health is not limited to drug markets and drug user networks; for example, recent work has argued for a connection between historical patterns of disenfranchisement among blacks in the southern U.S. and rates sexually transmitted infections in the present (Thomas, 2006). This paper examines patterns connecting race, travel between neighborhoods, role in syringe distribution networks, and neighborhood history.

PPP syringe distribution activities were concentrated in the Hill District, a neighborhood with high levels of drug activity that draws users from the rest of the city and the surrounding suburbs, as demonstrated by the data in this study. Among PPP participants, race and neighborhood of residence shaped how syringes moved through syringe distribution networks and across neighborhood lines. Both black and white respondents reported substantial network activity in the Hill District, but the patterns of interaction with networks members varied by race. Whites typically went to the Hill to acquire syringes that were then distributed to other white IDUs in their home neighborhoods, while blacks conducted the majority of their syringe acquisition and distribution activities in the Hill regardless of where they lived. Both of these travel patterns describe movement from areas with lower drug market activity to a high visibility drug market in order to obtain injection related supplies. These travel patterns raise questions about how neighborhood history shapes the development of high visibility drug market areas, and what the historical relationship has been between these contemporary drug market areas and other parts of the city.

The Hill District is located near downtown Pittsburgh, relatively distant from the manufacturing centers of the city, and has been a low income neighborhood since the late 19th century, when it was a target neighborhood for Eastern European immigrants. By 1930, the Hill District had become one of three disproportionately black Pittsburgh neighborhoods, and blacks’ arrival throughout the Great Migration and their inability to settle in white neighborhoods led to increased crowding (Darden, 1973). Given its proximity to downtown and economic marginality, the Hill has a long and complicated history as a center for both licit and illicit entertainment, from 19^th century brothels (Selavan, 1971) to famous jazz clubs (Reckless, 1969 (1933), serving patrons from throughout the city. Following World War II, the combination of de-industrialization (Babcock et al., 1998) and urban renewal left the neighborhood socioeconomically devastated, including the razing of a major social and commercial district for the construction of the Civic Arena (Bodnar et al., 1982; Lubove, 1995; Glasco, 1989). This history will be discussed in more detail towards the end of the paper, and raises interesting questions about how long term historical relationships between neighborhoods in a city may shape contemporary patterns of association and the social organization of drug activity.

This paper explores connections among race, network characteristics, and neighborhoods by examining how travel patterns between neighborhoods are associated with syringe distribution roles, network linkages across race and neighborhood lines, and the history of the neighborhood in which drug activity is most concentrated. After a brief description of the research methods, we summarize data from participants at the Prevention Point Pittsburgh (PPP) SEP, including patterns of travel between the neighborhoods and variation according to race. We also present data on drug-related policing activity within the Hill District and other areas of the city to support our contention that parts of the Hill can be considered a “high visibility drug market.” The discussion includes consideration of how the history of the Hill shaped its current condition and role within the city. In both historical and police activity data, we will draw comparisons between the Hill and the South Side, a predominantly white area where many white respondents in the study live, in order to explore the effects of historical processes and neighborhood contexts. Finally, we will consider the interaction of race, neighborhood, and selected forms of risk as part of a larger urban ecology of drug use.

Methods

In 2000–01, the authors conducted a case study of Prevention Point Pittsburgh, consisting of structured interviews with participants, semi-structured interviews with program staff (all volunteer except for a single employee), and limited participant observation. At the time, the SEP operated entirely underground, primarily through a system of secondary exchange. This program structure meant that IDUs’ social networks were intentionally integrated into, indeed central to, the outreach methodology for distribution and disposal of safer injection materials and health education. To reflect this outreach method, the study instrument included an assessment of respondents’ syringe distribution networks. The outreach strategy created few possibilities for participant observation, although the first author did accompany PPP volunteers on delivery rounds when possible. This paper is based on data about syringe distribution networks obtained as part of the structured interviews. All interviews were conducted in a private location by trained and experienced interviewers. This study was approved by the Institutional Review Board at Beth Israel Medical Center. All respondents provided informed consent prior to being interviewed, and were compensated $15 for participating in the study.

Syringe distribution networks were defined as the persons whom the respondent had given syringes to or received syringes from in the preceding 30 days. Other studies of drug user networks have examined risk networks, defined as those persons with whom the respondent has engaged in a potential risk event, such as injecting drugs or having sex, within a designated time period (Latkin et al., 1995; Latkin et al., 2004; Hoffmann et al., 1997; Friedman et al., 1999). While most network dyads in this study have a history of injecting together, syringe distribution may take place independently of an injection episode and respondents may have injection partners who are not part of their syringe distribution network. Therefore the syringe distribution networks described in this study have some similarities to risk networks, but are not the same. All network data collected and analyzed in this study are egocentric.

Recruitment

Respondents were recruited to the study through direct referral by program volunteers or chain referral by other respondents. In order to qualify for the study, respondents had to report regularly receiving PPP syringes during the last year, either directly from PPP volunteers or indirectly through secondary exchange/distribution; during an informal screening conversation, interviewers briefly explored the frequency with which potential respondents obtained syringes from different sources in the previous year, in order to assess the person’s direct or indirect relationship to PPP. In addition, much of the chain referral process involved asking a respondent to introduce us to the people to whom s/he gave syringes. Respondents did not have to be IDUs, but in practice almost all were current injectors. We did not code referral linkages between respondents.

Instrument

The study instrument was a fully structured, interviewer administered survey that assessed socio-demographics, neighborhood of residence, drug use, sexual behavior, HIV risk behavior, health status, and syringe distribution networks. To elicit the syringe distribution network, a respondent was first asked to list first names (or other anonymous identifier) of all the persons from whom the respondent had received syringes in the preceding 30 days, and then asked to list (anonymously) all the persons to whom the respondent had given syringes in the preceding 30 days. These lists were compiled, and the respondent prompted whether there was anyone else whom s/he had given syringes to or received syringes from in the designated time period. PPP volunteers were not included in syringe distribution networks, but contact with core distributors was included as these individuals did not consider themselves SEP volunteers. Once a final list was created, the respondent was then asked a series of questions about each network member, assessing demographics, duration and brief description of relationship, neighborhood in which respondent and network member usually meet, past sex and drug contact, and recent syringe transactions, including number of syringes given or received, and whether drugs, money, or sex were exchanged for the syringes. ‘Relationship’ was assessed by offering a list of descriptive words (e.g. acquaintance, friend) from which the respondent could choose, but a precise definition for each relationship term was not provided. Syringe transaction questions were asked separately for syringes given to and syringes received from each network member.

Core Distributors

In 1995, when PPP first began operations, exchange was conducted openly at a table on a street corner near the border of the Hill District and Uptown. The first person to exchange syringes was a middle aged black man named Mike, who lived less than a block away from the exchange site and ran a shooting gallery in the building where he lived. Over the next two years, Mike and a neighbor of his, Karen, took on increasing responsibility for distributing syringes and risk reduction information. In 1997, when political and police pressure forced PPP off the street, Mike and Karen became core distributors for the program, taking 70–80% of the syringes given out by PPP each week and collecting used syringes for disposal. Both Mike and Karen rejected any official identification as SEP staff or volunteers, and both participated in this study as respondents. From an organizational perspective, however, Mike and Karen occupy a complex and central role in the distribution system. In order to accurately examine the role of the core distributors within the larger system, network data from Mike and Karen has been analyzed and presented as a distinct subset.

In addition to their self-reported networks, Mike and Karen were explicitly named by just over half of other respondents as a source of syringes in the preceding 30 days. This data provides information about Mike’s and Karen’s distribution activities as well as their roles within the social network’s of other respondents. These reports by others cannot be matched to Mike or Karen’s self report, as they listed network members anonymously and linkages between referrals were not coded. In addition, interviews were conducted over a 12 month period, while network data from each respondent is limited to the preceding 30 days. Therefore, a respondent’s report of contact with Mike, for example, would not necessarily have taken place within the time frame referenced by Mike’s ego-centric network data. The two data sources agree that all contact between Mike or Karen and network members occurred in the Hill or Uptown neighborhoods, and the majority of contacts involved network members visiting Mike’s or Karen’s homes, including Mike’s shooting gallery. Respondents who reported contact with either of the core distributors have some distinct network characteristics, and tables present data on contact with core distributors separately from contact with other network members, in order to more appropriately capture the particular network locations of these two individuals.

Missing Data

Respondents were able to provide varying levels of detail about network members. Given the focus of this analysis, network records that were missing race and/or rendezvous neighborhood were excluded. In addition, although this is not “data cleaning” in the usual sense, a few respondent and network records were excluded from this analysis on the basis of race. Over 95% of respondents identified as either black or white. Respondents who identified as Latino, Other, or for whom race is missing were not used in order to facilitate concentration on the race-neighborhood patterns in the majority populations. Including the core distributors, 50 white and 101 black respondents reported a total of 671 network members. Forty-seven (7%) of the 671 network records were missing race or neighborhood data, and therefore excluded from this analysis. Of the resulting 624 network members, 110 (19%) were reported by the core distributors, Mike (N=82) and Karen (N=28), and data on this population is presented in Table 5. The remaining 514 networks, reported by 50 white and 99 black (excluding Mike and Karen) respondents, are discussed in Tables 3 and 4, and Figure 1. However, Table 4 and Figure 1 focus on patterns of syringe distribution and travel among black and white respondents and network members, and therefore do not include data regarding 11 network members described as latino.

Neighborhood Coding

Pittsburgh has “neighborhoods” with sufficiently well recognized boundaries that they are marked on a standard city map and referenced in historical texts. Respondents were asked to identify the neighborhood they had lived in during the preceding six months, and the neighborhood in which they most often met each network member. We did not obtain more precise locational data, such as specific parks, street intersections, or addresses for residence or other activities. This methodology reflected both our research questions, which were framed in relation to neighborhoods and not subsets of neighborhoods, and the practical realities of daily life for the respondents. Many respondents were episodically homeless or transiently housed, typically resulting in frequent moves within a neighborhood but no long term fixed address, and syringe distribution activities were also not necessarily based at a single stable location. Respondents could more consistently provide reliable neighborhood-level information, and this seemed entirely adequate for the research questions posed for this study. However, this means that the neighborhood data collected in this study were not as detailed or precise as is often utilized with GIS or other contemporary geographic analysis.

Data on respondent residence and respondent-network member rendezvous were coded first according to these neighborhoods, and then gradually consolidated into six composite areas. The first round of coding, prior to any consolidation, resulted in 30 neighborhoods among 151 respondents, with substantial clustering and many neighborhoods with a very small number of respondents. Codes were gradually consolidated on the basis of common social and historical characteristics. The Hill and Uptown border each other and had the largest study population, but were collapsed into one category “Hill/Uptown,” as respondents explicitly treated them as a socially continuous, even interchangeable, unit. The South Side and Lawrenceville were grouped together as both are historically white working class neighborhoods. The North Side and Oakland were grouped together as both are relatively integrated. The three remaining categories – Other Black, Other White, and Other – are essentially residual groupings of neighborhoods that each had a small number of respondents (N = 1 to 6). Other Black and Other White, as their labels suggest, were sorted based on racial classifications; for example, Homewood-Brushton and East Liberty are historically black Pittsburgh neighborhoods included in Other Black. “Other” aggregates Don’t Know/Refuse, Jail, and a few suburban areas.²

Network Coding

As we did not code referral linkages between respondents and all data are anonymous, it is not possible to link network data from one respondent to survey data from another respondent. The only exception occurs when respondents explicitly named one of the core distributors as part of their syringe distribution network, as described above, and respondents were coded as to whether or not they reported receiving syringes from Mike or Karen. All network dyads were coded by race of respondent and race of network member; for example, a dyad coded white-white consisted of a white respondent and white network member, while one coded black-white consisted of a black respondent and a white network member.

Respondents were coded according to their role within their syringe distribution network. A small number of respondents, categorized as “Suppliers,” only receive syringes directly from the SEP, and do not report receiving syringes from any network members. “Endpoints” are respondents who report receiving syringes from one or more network members, but do not report giving syringes to anyone in the last 30 days. “Transit Points” are respondents who report both receiving syringes from and giving syringes to network members. Respondents were also coded as to whether they receive syringes from one person or multiple people.

Data Analysis

The analyses performed for this paper were primarily descriptive. We began with a comprehensive data report with frequencies and means of all variables, and cross-tabulation of variables of interest, particularly in regard to the relationships between race, neighborhood of residence, network roles, and contact with core distributors. In addition, we created charts with race, neighborhoods of residence and rendezvous, and syringe transaction in order to visually examine patterns in the data regarding these variables (resulting in Figure 1). We used Chi-square tests and T-tests for statistical significance for racial differences among respondents on selected variables, as indicated in the tables. Data were analyzed using SPSS version 13. As with qualitative data, the coding systems themselves constitute a form of data analysis.

Historical and Policing Data

The historical discussion in this paper primarily draws on published histories of migration, neighborhood formation, entertainment venues, and drug policy. In addition, US Census tract maps were examined for each decade from 1940 to 2000, and tracts corresponding to the Hill District and the South Side were identified. Data on demographic and housing characteristics were abstracted for each Census decade for the Hill and South Side tracts. The police data consists of drug offenses, derived from the Police Department’s database, and 911 calls for 2000 and 20001, presented by 1990 census tracts. This data was compiled for another study, and generously provided to us by a colleague (Jacqueline Cohen, Carnegie Mellon Univ., personal communication).³

Results/Findings

The Hill District as a High Visibility Drug Market

While a full exploration of drug activity in the Hill District is beyond the scope of this paper, limited data on drug activity can support classification of the Hill as containing both significant and visible drug market activity. As can be seen in Table 1, at the time this study began multiple tracts in the Hill had substantially elevated rates of both 911 calls and drug offenses when compared to the remainder of the Hill, the South Side, and the overall city averages. While this does not definitively satisfy all the elements of Ford and Beveridge’s definition of a “high visibility drug market,” it indicates an elevated level of drug activity as perceived both by 911 callers, suggesting visibility, and the police. Visual inspection of the environment during data collection supports the other elements of the definition, with observation of high levels of visible drug buying and selling, many boarded up buildings and empty lots, and few socially productive businesses. According to newspaper accounts, the Hill District has not had a grocery store since 1987 (Dyer, 2003).

Table 1.

Drug Offense and 911 Call Data for the year 2000, by Census Tract

Census Tracts	Drug Offenses	Drug Related 911 Calls
Hill District Tracts
305	9	14
314	138	121
501	140	172
502	15	9
506	8	17
508	1	5
509	88	79
510	67	80
511	96	99
South Side Tracts
902	14	41
1609	9	10
1702	20	34
1704	0	2
2019	2	12
2020	13	25
City-wide Average	16	19

Respondents and Network Members

As can be seen in Table 2, there are substantial socio-economic differences between white and black respondents. Overall, black respondents are significantly older, less likely to have finished high school, and more likely to have ever been incarcerated. White and black respondents are equally likely to have been homeless at some point during the previous six months, but there are significant racial differences in where respondents lived most during that time. Rates of daily injection are similar across race, as are rates of selling sex.

Table 2.

Demographic Characteristics

	White (N=50)		Black (N=101)		p value
	%	N	%	N
Age (M, SD)	32.0	10.1	40.6	9.6	< .001
Gender					n.s.
Male	62%	31	60%	60
Female	38%	19	40%	40
Completed High School or GED	94%	47	53%	53	< .001
Injected daily, last 30 days	76%	38	80%	79	n.s.
Sex work, last 30 days	20%	10	29%	29	n.s.
Income from illegal source, last 6 months	56%	28	64%	65	n.s.
Ever in jail (lifetime)	44%	22	87%	88	< .001
Ever homeless, last 6 months	12%	6	11%	11	n.s.
Where lived most, last 6 months					< .004
In own house	71%	35	40%	40
In someone else’s house	20%	10	41%	41
In hotel, rooming house, shelter	4%	2	8%	8
On streets or in a shanty	2%	1	-	-
In jail	2%	1	9%	9
Some other place	-	-	3%	3
Neighborhood of Residence					< .001
Hill/Uptown	4%	2	46%	46
Black neighborhoods	2%	1	28%	28
Southside/Lawrenceville	26%	13	3%	3
White neighborhoods	24%	12	2%	2
Northside/Oakland	36%	18	14%	14
Other	8%	4	8%	8

Neighborhood of residence reflects larger patterns of racial segregation in Pittsburgh. Black respondents primarily live in the Hill/Uptown or other predominantly black neighborhoods in eastern Pittsburgh (e.g., Homewood, East Liberty). White respondents are more evenly distributed across several neighborhoods. The neighborhoods of the North Side and Oakland, grouped together into one code, are relatively integrated both in this dataset and at the population level, with just over 1/3 of white respondents and 14% of black respondents residing in these neighborhoods.

Table 3 provides summary data on the characteristics of network members (persons named as syringe distribution contacts), by race of respondent. As noted above, black respondents are older than whites (Table 2), and the same is true for their network members. Dyads tend to be racially homophilous, excluding white respondents’ contact with the core distributors which will be discussed in table 4. Black respondents are more likely to describe network members as “acquaintances,” while whites are more likely to use “friend,” yet the average duration of relationships for both groups is similar and indicates relatively longstanding relationships. Most of these dyads have a history of injecting drugs together, but few have had sex.

Table 3.

Characteristics of Network Members (N= 431) and Syringe Transactions^*

	White Respondents (Dyad N=122**)		Black Respondents (Dyad N=309)**		p value
	%	N	%	N
Age (M, SD)	34	10.7	40.4	9.1	< .001
Gender					n.s.
Male	71%	85	67%	206
Female	29%	35	33%	103
Missing		2
Race
White	79%	96	18%	54
Black	21%	26	79%	244
Latino	0	0	3%	11
Relationship					< .001
Acquaintance	19%	23	49%	150
Friend	64%	78	35%	106
Other	17%	21	17%	51
Years of relationship (M, SD)	8.6	9.2	9.2	7.9	n.s.
Ever injected with respondent	71%	86	77%	239	n.s.
Ever had sex with respondent	10%	12	17%	52	n.s.

^*Does not include data from Core Distributors (110 dyads), or describing contact with Core Distributors (83 dyads)

^**Dyads represent respondent-network member pairs, so the white dyad N of 122 indicates that the white respondents collectively named 122 persons (not including Core Distributors) with whom they engaged in syringe distribution transactions. African American respondents collectively named 309 persons, excluding Core Distributors, with whom they engaged in syringe distribution transactions.

Table 4.

Syringe Transactions by Race of Respondents (N=149) and Networks (N=503)^*

4a. Transactions with Network Members Other Than Core Distributors
	White Respondent-White Network Member Dyads		White Respondent-Black Network Member Dyads		Black Respondent –White Network Member Dyads		Black Respondent -Black Network Member Dyads		p
	Dyad N=96		Dyad N=26		Dyad N=54		Dyad N=244
	%	N	%	N	%	N	%	N
Respondent gave syringes	91%	87	42%	11	93%	50	33%	81	< .001
Received money**	76%	66	64%	7	72%	36	59%	48	<.05
Received drugs**	34%	30	36%	4	44%	22	40%	32	n.s.
Received sex**	6%	5	18%	2	16%	8	6%	5	n.s.
Respondent received syringes	9%	8	70%	16	46%	25	77%	187	< .001
Gave money**	88%	7	68%	13	16%	4	72%	135	< .001
Gave drugs**	0	0	5%	1	36%	9	24%	44	<.05
Gave sex**	0	0	0	0	0	0	1%	2	n.s.
4b. Transactions with Core Distributors
	White-White Dyads		White-Black Dyads		Black-White Dyads		Black-Black Dyads
	N/A		Dyad N=33		N/A		Dyad N=50		p
			%	N			%	N
Respondent received syringes			100%	33			96%	48	n.s.
Gave money**			61%	20			88%	42	<.05
Gave drugs**			42%	14			68%	34	<.05
Gave sex**			3%	1			0	0

^*Excludes data on Hispanic network members and data reported by Core Distributors

^**Exchange of money, drugs and sex for syringes asked as separate Yes/No questions. Percentage and N listed in table represents “Yes” responses to each variable.

Syringe transactions vary by the race of both respondent and network member, and Table 4 shows syringe transactions for racially homophilous and non-homophilous dyads. There are separate columns for each dyadic combination of respondent race and network member race, with respondents’ race coming first in the pairing as indicated in the column headings. There is a strong pattern of syringes flowing from blacks to whites: excluding contact with core distributors (section 4a), 93% of black-white dyads and 70% of white-black dyads involve whites receiving syringes from blacks, although some of these dyads also report transactions in the other direction. As the core distributors were black, this pattern becomes even stronger when contact between respondents and core distributors is included (section 4b of table). When contact with core distributors and other network members is aggregated, dyads in which blacks give syringes to whites accounts for 83% of all cross-race dyads (not shown separately in table). In same-race contacts, white respondents report primarily giving syringes to white network members (91% of dyads), while black respondents are more likely to receive syringes from black network members (77%). Respondents are more likely to get money when they give syringes to white network members than to black; however, when respondents receive syringes, they are more likely to pay for them when receiving from same race network members.

Core Distributors

Both core distributors participated in the study as respondents, and data on their self-reported syringe distribution networks is summarized in Table 5. Mike received the majority of the syringes distributed by SEP personnel each week, and in the 30 days preceding the interview he gave those syringes to 82 people. Karen reported a total network of 28; she gave syringes to 27 people in the previous 30 days, and received syringes from one (Mike), as well as from the SEP. She was enrolled in a methadone program at the time of the interview and she had told SEP staff that this limited her activities. Both Mike and Karen had networks that were almost entirely black, and describe ¾ or more of them as “acquaintances.” In spite of this, Mike had known the people he distributed syringes to for an average of 25 years and Karen for 14 years. Mike reported often giving syringes without receiving anything in return, although he also frequently received money or drugs. Karen almost always received money and/or drugs.

Table 5.

Network Members and Syringe Transactions for Core Distributors

	Mike’s Network (N = 82)		Karen’s Network (N = 28)
	%	N	%	N
Gender
Male	70%	57	64%	18
Female	28%	23	36%	10
Transgender	2%	2	-	-
Race
White	10%	8	7%	2
Black	88%	72	93%	26
Latino	2%	2	-	-
Relationship
Acquaintance	92%	73	75%	21
Friend	-	-	25%	7
Other	8%	9	-	-
Years of relationship, Mean (SD)	24.8 (14.8)		13.9 (10.2)
Ever injected with network member	100%	80	100%	28
Ever had sex with network member	1%	1	4%	1
Syringe transactions, last 30 days
Gave syringes	100%	80	96%	27
Received money*	22%	19	93%	26
Received drugs*	43%	35	89%	25
Received sex*	-	-	-	-
Received syringes	-	-	4%	1
Gave money*	-	-	4%	1
Gave drugs*	-	-	-	-
Gave sex*	-	-	-	-

^*Exchange of money, drugs and sex for syringes asked as separate Yes/No questions. Percentage and N listed in table represents “Yes” responses to each variable.

Network Attributes and Roles

Table 6 summarizes key elements of network attributes by race of respondent, and by whether the respondent reported contact with one of the core distributors. Whites were more likely than blacks to receive syringes from Mike or Karen, and less likely to receive syringes from multiple sources. Among white respondents, those who received syringes from the core distributors reported no other sources of syringes, while similar proportions of blacks reported multiple syringe sources regardless of contact with core distributors. The majority of network contacts were racially homogenous, but whites were more likely than blacks to report any cross-race contact. It is worth noting, however, that a somewhat higher proportion of blacks who received syringes from Mike or Karen reported cross-race contact, compared to other blacks. Whites were more likely than blacks to function as Transit Points, receiving syringes from one or more network members and giving to others. Within racial groups, respondents who received syringes from one of the core distributors were more likely to be Transit Points than other respondents. In general, whites tended to have a single source of syringes, typically one of the core distributors, and then supplied those syringes to a small network. In general, blacks tended to have multiple sources of syringes, were rarely dependent on the core distributors, had less cross-race contact, and were more likely to be Endpoints within their networks.

Table 6.

Network Attributes and Roles (including Core Distributors)

	White		Black		p value
	%	N	%	N
All Respondents	N = 50		N = 101
Network Size (M, SD)	3.5	2.4	4.9	8.6	n.s.
Received Syringes from Core Distributors	66%	33	50%	50	.055
Any cross-race network members	82%	41	20%	20	< .001
Cross-race contact excluding core distributors	44%	22	N/A	N/A
Receive syringes from multiple network members	16%	8	70%	71	< .001
Respondents who received syringes from Core Distributors	N = 33		N = 50
Network Size (M, SD)	3.1	2.1	5.0	5.0	.048
Any cross-race network members	100%	33	24%	12	< .001
Cross-race contact excluding core distributors	36%	12	N/A	N/A
Role					< .001
Supplier (only give)	0	0	0	0
Endpoints (receive only)	15%	5	52%	26
Transitpoints (give & receive)	82%	27	46%	23
Receive syringes from multiple network members	0	0	68%	34	< .001
Respondents who did not receive syringes from Core Distrib.	N = 17		N = 51
Network Size (M, SD)	4.1	2.8	4.9	11.1	n.s.
Any cross-race network members	59%	10	16%	8	.001
Role					.022
Supplier	6%	1	10%	5
Endpoints	29%	5	53%	27
Transitpoints	65%	11	35%	18
Receive syringes from multiple network members	35%	6	73%	37	.014

Neighborhoods, Travel, and Race

Figure 1 presents neighborhood data for respondent residence, and for rendezvous of racially homophilous and non-homophilous dyads by race of respondent. Figure 1a has data for white respondents and Figure 1b for black respondents. Figures 1a and 1b include rendezvous with the core distributors, but do not include data reported by the core distributors. Color coding of bars is by race of network member; grey bars reflect meetings with white network members, black bars meetings with black networks members, and white bars reflect residence of respondent. Looking at both Figures 1a and b, it is immediately apparent that the majority of rendezvous with black network members occurred in the Hill/Uptown, regardless of race of respondent. Some white-black rendezvous occurred in all neighborhoods, for both white and black respondents, but were concentrated in Hill/Uptown and secondarily in NorthSide/Oakland, the relatively integrated neighborhoods. Racially homophilous contacts occurred in a more restricted range of neighborhoods, following overall lines of residential segregation; there are few white-white meetings in majority black neighborhoods or black-black meetings in predominantly white neighborhoods. In combination with the data in Table 4, on cross race contact and syringe distribution, the data in Figure 1 highlight the role of white transit points in moving syringes from black neighborhoods and network members to white neighborhoods and network members.

Figure 1.

Residence Neighborhoods of Respondent and Neighborhoods of Rendezvous with Network Members*

Figure 1a. White Respondents

Figure 1b. Black Respondents

H/U: Hill/Uptown, BN: Black Neighborhoods, S/L: Southside/Lawrenceville, WN: White Neighborhoods, N/O: Northside/Oakland

* Includes rendezvous with the Core Distributors, as reported by respondents, but does not include data reported by Core Distributors

Discussion

These data on networks and neighborhoods shed light on the social location of a neighborhood that contains a high visibility drug market within the larger ecology of drug user networks spanning multiple neighborhoods of a city. Respondents who lived in other neighborhoods obtained syringes in the Hill/Uptown, and respondents who acted as Transit Points in their networks then distributed those syringes to other users. Travel patterns and network transactions were racially distinct; black respondents conducted almost all of their syringe transactions in the Hill/Uptown, regardless of network role, while whites generally had only one contact in the Hill/Uptown, most commonly one of the core distributors but sometimes with another black person. The core distributors appear to play a particularly central role in the networks of white respondents, acting as sole source of syringes for two thirds of white study participants overall and almost three quarters of white Transit Points. In non-homophilous dyads, syringes flowed from blacks to whites, and white Transit Points then generally distributed these syringes to white network members in predominantly white neighborhoods. The main exception to these racial patterns involves black Transit Points who lived in the integrated areas of North Side/Oakland, who had some elements of a ”white” travel and network contact pattern. This group of black respondents also obtained syringes in the Hill/Uptown, had high levels of contact with the core distributors, and engaged in some syringe distribution activities in their home neighborhood, including substantial contact with white network members.

In distribution transactions, money and/or drugs were commonly exchanged for syringes, including in contact with the core distributors. The long-term nature of the relationships suggests that these were not purely commercial “syringe sales,” certainly not of the anonymous street variety. Snead et al. (2003) found that secondary exchange takes place through longstanding social networks, and occurs in the context of a complex web of favors, drug sharing, and other forms of mutual aid. This is also in keeping with decades of social research on low income communities overall, which consistently finds significant resource sharing, including money, childcare and food (e.g. Stack, 1974; Edin and Kefalas, 2006). Drug user ties are often stereotyped as both exploitive and transient in nature, and while we cannot speak to the emotional content of these relationships, it should be noted that the drug users in this study were actively engaged in public health activity that benefited both their personal associates and their larger communities, and that this activity was not without legal risk. As many who work professionally in public health know, material interest and altruism commonly co-exist, with the former underwriting the latter to enable the construction of careers. The combination of altruism and commercial exchange reflected in the syringe distribution activities of respondents in this study speaks to the complex motivations that underlie deviant careers, no less than professional ones. This is particularly true in relation to the core distributors, and the central role they took on in working closely with SEP staff in order to supply sterile syringes to the networks described here that extended throughout a major city.

Travel Patterns, Neighborhoods and Risk

The social network data in this study describe two different patterns of movement between low and high visibility drug market neighborhoods. In one pattern, the majority of drug activity is concentrated within the neighborhood containing high visibility drug market activity; in the other pattern, contact is made within the high market-visibility area and supplies are brought back for circulation in the lower market-visibility areas. In this dataset, these patterns are racially coded, with the former strategy most common among blacks and the latter among whites.

These racial-geographic patterns to the movements of people and syringes raise questions about network activity, travel, and risks related to syringe supply and legal sanction. Drug users face multiple forms of risk, some of which derive from a substance itself (e.g., addiction, overdose) but others of which derive from social or societal factors (e.g., stigma, arrest, use of non-sterile syringes). Syringe distribution networks directly address risks related to syringe supply, specifically access and sterility. In the absence of legal and widely available syringe exchange, these two forms of supply risk may be inversely related; having multiple sources of syringes reduces the risk of loss of access, but each different source brings some probability (however small) of receiving an un-sterile syringe. It is worth noting that contact with the core distributors functionally eliminated the risk of receiving an unsterile syringe for white respondents, as they report no other syringe sources and Mike and Karen were a direct extension of the SEP. In contrast, black respondents were equally likely to receive syringes from multiple sources regardless of contact with the core distributors.

Syringe distribution encounters in themselves create potential occasions for legal risk, as an illegal activity is taking place. It should be noted that arrest brings its own, distinctive, syringe supply problems. While it is not possible to know the precise details (e.g., indoor vs. outdoor) of every distribution encounter contained within the network data, the neighborhood within which the encounter takes place offers some indication of the probability of police attention. A comparison of Table 1 and Figure 1 reveals that the neighborhood with the highest frequency of white-white rendezvous had generally low levels of drug related police activity and 911 calls, while the majority of rendezvous involving blacks occurred in the Hill/Uptown, where there is substantial policing activity. In addition, blacks are disproportionately likely to experience incarceration or otherwise be under supervision of the criminal justice system, particularly as a result of drug offenses (Currie, 1993), as reflected in the black-white differences in lifetime incarceration rates in this study (Table 2). Therefore, syringe distribution activities in the Hill/Uptown and/or by blacks may bring elevated levels of legal risk, particularly when the two are combined.

In this study, the potential risks associated with syringe distribution activity vary by race. Blacks have multiple sources and contacts, and their activities are concentrated within the Hill. This strategy reduces access-associated risks, absent arrest, but increases the potential for encountering an un-sterile syringe and for police attention. Whites demonstrate the opposite pattern; they are more likely to be vulnerable to loss of supply, having only one source, but thereby limit the probability of un-sterile syringes, particularly if their source is Mike or Karen. The white travel pattern may reduce legal risk by limiting activity in the Hill/Uptown and conducting much of their syringe distribution in areas with lower levels of police attention.

The racial structure of syringe distribution networks raises interesting questions about neighborhoods, network bridging and the organization of both syringe supply and legal risks. Curtis et al.’s (1995) study of a drug market area found that members of the core network used their high levels of participation in the drug market to facilitate brief contacts by peripheral members, who could quickly obtain supplies and leave. The role played by Mike and Karen, particularly for white respondents, is analogous to that of some members of the core network in Curtis et al, with the vital exception that the core members in Curtis’ study did not obtain all their supplies from a SEP. In Curtis et al.’s study, these network structures were not described as racialized, but they bear a strong resemblance to the pattern of interaction between blacks and whites noted here. In both cases, a highly visible drug market area creates a venue for network bridging, but in a location that may concentrate certain forms of legal risk due to high levels of police attention. The racial patterning of contact in this study indicates that some blacks are absorbing legal risks, through their activities in the Hill, that position them to occupy a very particular network role that enables some containment of both legal and syringe supply risks within white drug user networks. The extremely low rates of cross-race contact in non-integrated white neighborhoods, and black neighborhoods with less visible drug activity, supports the argument for high visibility drug markets as a zone for network bridging, particularly inter-racial contact. Given that the majority of network dyads in this study have a history of injecting together, and the role of network bridging in the spread of HIV (Williams et al., 2005; Kottiri et al., 2002), a social or geographic location that enables network bridging among IDUs could have significant public health implications in regard to control of HIV and other blood borne infections. These locations could be zones for either the transmission of disease across communities or, as in this study, peer-based implementation of a vital public health intervention. These findings support the need for easy access to sterile syringes in areas where multiple IDU networks interact.

Networks, Drug Markets, and Neighborhood History

If particular neighborhoods become zones for inter-racial drug-related contact and network bridging, this raises questions about the historical development of these neighborhoods both as specific locations and within a larger urban ecology. For over 100 years, the Hill has played a role as a center for stigmatized and/or illicit pleasure-oriented businesses -- such as speakeasies, dope dens and brothels – which served patrons from outside the neighborhood. In 1900, the Bureau of Police cited the Lower Hill District’s location adjacent to downtown to explain the large number of brothels there; they reported having closed down 268 establishments that year alone (Selavan, 1971). A number of years later, Alexander Pittler (1930) developed a set of maps showing the distribution of “brothels and assignation houses,” “speakeasies, dope dens, and stills,” “gambling dens,” “pool rooms,” and “pawnshops” in the Hill District. Pittler distinguished between venues that catered to blacks or whites, with those catering to whites clustered along the border with downtown and major traffic arteries leading to it. The location and race of clientele for many of these establishments suggest that their customer base included residents from outside the Hill District, as does the Bureau of Police report from 1900.

The concentration of such venues notwithstanding, there were important differences between the Hill District of the 1930s and that of the 1990s. While markets in drugs, sex, and gambling were disproportionately concentrated in the Hill in the 1930s and earlier, they did not stand out in the ways that visible drug markets do today. Drug sales and gambling often occurred within licit business venues such as pool rooms and bars (which resumed legal status after repeal of alcohol prohibition in 1933) (Reckless, 1969 (1933)). Outsiders who came to the neighborhood to drink, gamble, or consort with prostitutes often spent an evening at venues such as cabarets or black and tan clubs in which black jazz bands and dancers performed for white audiences (Reckless, 1969 (1933)). This suggests that outsiders came for an evening’s entertainment, not for quick, furtive drug purchases as they do today. Such venues, in turn, sat side by side with grocery stores or laundries; the densely populated, racially mixed neighborhood was also home to mutual benefit societies, social clubs, and other secular and religious institutions of civic life (Bodnar et al., 1982; Glasco, 1989). Licit and illicit businesses were mutually supportive in multiple ways; not only did they often serve the same clientele, but money generated by illicit enterprise, such as a highly profitable “numbers running” system, accumulated capital that could be loaned out to neighborhood residents (Glasco, 2004). Today, there is a striking lack of legal businesses and entertainment venues in the Hill, making illicit markets the primary form of commerce. Ford and Beveridge (2004) identify this as one of the defining characteristics of high visibility drug market areas.

Comparing the Hill District to the South Side, where many white respondents in this study lived and the majority of white-white dyads met, emphasizes both the race-related disadvantages suffered by Hill residents and how different neighborhood development paths might lead to contemporary network travel patterns. As noted earlier, the Hill District has long been a low income neighborhood, and was far from the manufacturing centers of Pittsburgh at the time of the city’s industrial prime. In the 19^th and early 20^th centuries, the Hill provided an initial home for new European immigrants as well as blacks migrating north, but European immigrants moved on to other, better situated, Pittsburgh neighborhoods while blacks had fewer residential options (Bodnar et al, 1982). In contrast, the South Side is located immediately south of the Hill District across the Monongahela River, near to the (now largely closed) steel mills along the riverfront that provided the unionized industrial jobs that were the economic mainstay of this largely Polish neighborhood. The maps created by Alexander Pittler (1930) show similar rates of juvenile delinquency in the South Side and the Hill District, but the South Side did not have the organized vice establishments of the Hill. By 1940, the South Side was largely a stable second-generation neighborhood with relatively high rates of home ownership, while the Hill District had high residential turnover (Glasco, 2004; Bodnar et al., 1982). Employment and residential discrimination were thus key in shaping the relative economic and residential stability of these two neighborhoods.

In the second half of the 20^th century, de-industrialization exacerbated the longstanding economic disadvantages of blacks. The beginnings of deindustrialization were visible in declining employment levels in the region starting in the mid-1940s, and job loss became catastrophic with the collapse of the regional steel industry in the 1970s and 1980s. (Babcock et al., 1998) Differing rates of home-ownership, vacancy, and boarded-up structures indicate the growing social and economic gap between the Hill and the South Side, with ongoing home ownership and housing maintenance in the South Side and housing transience, increasing vacancy rates, and boarded up structures in the Hill (U.S. Census, 1942, 1952, 1962, 1972, 1982, 1992, 2002). As in other American cities, black neighborhoods in Pittsburgh bore most of the negative impacts of the urban renewal projects of the 1950s and 1960s. One central element of urban renewal in Pittsburgh was the construction of the Civic Arena in the Lower Hill, destroying an area that had been central to the life of the Hill District overall and that contained cultural institutions, social clubs, churches, and legitimate businesses (Bodnar et al., 1982; Lubove, 1995). In contrast, the South Side and other white working class areas were relatively unaffected by urban renewal, and may have indirectly benefited from the construction projects that devastated the Hill (e.g., employment, new recreational opportunities). Today, while the South Side shows some drug activity, it has not developed the highly visible drug markets that characterize much of the Hill, and maintains a functioning infrastructure of legitimate commercial establishments, including restaurants, bars, and trendy shops that draw customers from across the city. The comparison between the Hill and South Side suggests that analyses of the relationship between social policy, drug use, and drug markets needs to go beyond the traditional focus on drug laws and criminal justice, and consider a wider range of policies affecting social and economic development.

The travel patterns of respondents in this study suggest ways that neighborhood histories shape the lives of contemporary IDUs, through the social and economic paths of development that create different levels of visible drug market activity. Employment, home ownership, population stability or transience, and the development of local business are all deeply interconnected, shaping the presence or absence of the factors Ford and Beveridge found associated with the relative visibility of drug-related activity. While the connection between these historical processes and contemporary conditions may seem self-evident, and are not properly a ”finding” of this study, it is useful to explicitly consider the link between neighborhood development and contemporary network activity. In the South Side, these historical factors led to a social and economic environment that pushed drug transactions into privatized contexts, such as personal contact between old friends. In contrast, the history of the Hill District involves the gradual creation of an environment marginal to mainstream social and economic opportunities, and having the central characteristics associated with highly visible drug markets. “Visibility,” rather than existence, of drug activity is a central issue; highly visible drug markets serve IDUs from throughout a city (Ford and Beveridge, 2004; Andrade et al., 1999) and its suburbs (Thorpe et al., 2001), and thereby enable drug activity to be less visible in these other areas. In this way, the existence of a high-visibility drug market allows other neighborhoods, which contain IDUs but prevent open market activity, to “outsource” social and economic risks associated with illegal drug sales.

Limitations

Research methodology shapes the data collected, and therefore study findings, in multiple ways. A study that examines travel patterns, syringe transactions and race would, ideally, construct a socio-metric map of the networks extending outward from the Hill/Uptown, which would illuminate the racial and neighborhood-based patterns in considerably more detail than we have done here. Despite the limitations of ego-centric network data, we believe the patterns found in this study are strong and consistent enough to support the arguments made here, and raise interesting questions for future research. We believe this provides an interesting analysis within the constraints of the methodology, particularly regarding the potential relationships between historical trends and contemporary network activity at the neighborhood level. Our analysis of the linkage between neighborhood development and contemporary network patterns is necessarily somewhat speculative, but raises interesting questions for future work. Linking historical and contemporary data across levels of analysis is by nature a methodologically challenging and often somewhat speculative endeavor.

Finally, one might expect to find that the Hill/Uptown appear to be the center of syringe acquisition, as we interviewed IDUs who receive syringes from a SEP originally based in that neighborhood. We have no doubt that this research methodology, and the structure of the SEP, amplified the centrality of the Hill/Uptown as a source of syringes for IDUs who live in other areas. However, we do not believe that the inter-neighborhood travel patterns and racial structure of syringe transactions in this data are primarily an artifact of our research method or created by the SEP itself. First, the SEP chose its location on the basis of existing high-visibility drug activity, and the observation that the area in question drew IDUs from all over Pittsburgh. Second, the average duration of the network relationships in this study indicates that they predate the opening of the first SEP site. Third, our findings are congruent with those of other studies of IDU social networks. Finally, the inter-neighborhood travel patterns described here are in accordance with the findings of ethnographic studies of drug trafficking neighborhoods (Andrade et al., 1999; Bourgois, 1996; Curtis et al., 1995) and a macro-level analysis of the relationship between neighborhood characteristics and the visibility of drug activity.

Conclusion

The current survey was carried out in the context of an underground SEP with no fixed site of operations. Its findings demonstrate the ability of IDU networks to distribute syringes to injectors in multiple neighborhoods through extended secondary exchange transactions, and therefore support the value of secondary exchange, particularly in such a setting. Moreover, such success as the program did achieve depended crucially on the work of the core distributors, as the number of people they distributed syringes to attests, further indicating the clear utility of secondary exchange and use of IDU networks to extend the reach of SEPs. Even when SEPs are legal and located nearby, some IDUs resist attending them, whether because work or other commitments still make them inconvenient, or because a person fears possible recognition as an IDU while seeking needle exchange services (Murphy et al., 2004). Secondary exchange, then, appears to contribute to SEP effectiveness regardless of the legal status of programs and, as can be seen in this study, has the potential to distribute syringes across diverse social and physical spaces.

As research subjects, drug users are typically portrayed as objects of policy concern—criminals, potential clients for drug treatment or other programs, targets of public health outreach. Less commonly, ethnographers and historians have described drug users as persons in whose lives drug use is but one aspect—even if sometimes a dominant one. These findings reflect that perspective as well, as they show that network connections through which syringes were distributed were rarely just relationships of convenience, but were often longstanding relationships between friends or neighbors. Further, these findings point to the role that drug users can play in public health outreach through secondary exchange. Managing a career as an illicit drug user requires maintaining clandestine networks that ensure access to the illicit market. SEPs have taken advantage of such networks by locating near visible drug markets. With respect to the typical travel pattern of whites in this survey, this means SEPs are more likely to connect with network members who come there to buy drugs—and acquire syringes—for themselves and others. SEPs located near drug markets also become part of the broader set of resources available to persons who are marginal to mainstream society, like many blacks living in the Hill and the members of the core in Curtis et al. (Curtis et al., 1995) who spend a substantial amount of time in high visibility drug market areas.

The role of neighborhoods as a factor shaping IDU networks suggests that a range of urban policies affect IDU networks through the medium of neighborhood development. The socio-economic conditions that give rise to highly visible drug markets result from certain patterns of development that are shaped by a wide range of social policies, including housing, employment, transportation, policing, and urban renewal. Specifically, the data from this study indicate that the existence of those drug markets shape network activity, including racial variation in the experience of both legal and supply risks among IDUs from multiple neighborhoods scattered throughout the city. This study also raises questions about how neighborhood characteristics shape cross-racial contact within networks, as the majority of cross race rendezvous take place in drug market or integrated areas. Examining the role of neighborhood characteristics and history in shaping contemporary IDU networks adds to our understanding of how social context affects drug-related risks for both individuals and neighborhoods. The findings from this study challenge us to think about the ways that “risk management” in one context, such as the suppression of drug market activity in economically stable neighborhoods, displaces those hazards onto other, more vulnerable, contexts and communities, including the social hazards of highly concentrated illegal activity and the potential health hazards associated with having to travel extended distances to acquire sterile injection equipment. This pattern suggests that policies that contribute to the isolation or under-development of one area or population shape patterns of interaction and behavior across a wide social and geographic spectrum.

The combination of contemporary and historical data presented in this paper illustrates some of the connections between long-term patterns of discrimination and marginalization and contemporary patterns of legal and health risks for IDUs. However, these data on network structures and syringe distribution also demonstrate the ability of IDUs to form longstanding social ties across racial and neighborhood boundaries, and to use these connections to support HIV risk reduction through multiple neighborhoods of a major city. The IDUs in this study, and members of their social networks, responded to a grassroots public health intervention by taking on substantial responsibility for syringe distribution and disposal, sometimes traveling considerable distances carrying illicit “paraphernalia” in order to support safer behavior by friends and associates. These activities were largely facilitated by, and even dependent on, the work of the core distributors and other marginal IDUs living in an impoverished, isolated neighborhood who provided supplies to people coming in from other parts of the city.

Few, if any, of the participants of this study would be considered truly ”privileged” by American standards. However, the interactions that residents of both white working class and relatively intact black neighborhoods have with the Hill/Uptown illustrate the complex dependencies of the relatively more privileged on the relatively less privileged, particularly in regard to activities considered socially stigmatized, marginal, or dangerous. The risk management strategies of one neighborhood or social network are intimately linked to the historical and contemporary risk absorption of other, more vulnerable, neighborhoods and social networks.