Table 2.
Body burden (blood, urine, total body levels), minimum risk levels, and exposure limits for environmental contaminates in healthy individuals.
| Environmental Contaminants | Name | Levels in Blood, Urine (Mean/ Range) | Total Body Level | Minimal Risk Levels (MRLs) | Exposure Limits* | Reference | |
|---|---|---|---|---|---|---|---|
| TOXIC METALS | |||||||
| Aluminum | Blood 1-3 µg/L Urine mean value 23.7 µg/L |
For 70 kg adult 30–50 mg/ kg body weight | 1 mg aluminum/kg/day for chronic oral exposure (≥365 days) |
NIOSH REL TWA 10 mg/m3 | [205, 207] | ||
| Arsenic | ≤ 1 ppm in nails ≤ 1 ppm in hair Blood < 1 μg/L in Urine 0.0-35 µg/L |
Toxicity of arsenic depends upon exposure | 0.005 mg As/kg/day for acute oral exposure (≤14 days) to inorganic arsenic; 0.0003 mg As/kg/day for chronic oral exposure (≥1 year) to inorganic arsenic |
NIOSH REL TWA 0.002 mg/m3 | [23, 207] | ||
| Cadmium | Blood level 0.315 µg/L Urine level 0.193 µg/g creatinine (0.185 µg/L) |
For 70 kg adult, 10-50 mg/ kg body weight | 1 X 10-5 mg Cd/m3 has been derived for chronic inhalation exposure to cadmium (≥1 year). 3 X 10-5 mg Cd/m3 has been derived for acute- inhalation exposure to cadmium (≤14 days) |
NIOSH REL TWA 0.002 mg/m3 | [207, 208] | ||
| Cobalt | Blood levels 0.05–0.19 µg/dL Urine levels 0.04–2 µg/dL Air levels at unpolluted sites <1–2 ng/m3 |
For 70 kg adult, 1.1–1.5 mg/ kg body weight, with 0.11 mg in the liver. | 0.0001 mg cobalt/m3 for chronic inhalation exposure (>365 days) to cobalt 0.01 mg Co/kg-day for intermediate oral exposure (<365 days) |
NIOSH REL TWA 0.05 mg/m3 | [48, 207] |
||
| Copper | Serum copper 151.6 µg/100 mL Urine 18 µg/ g dry weight |
For 70 kg adult, 50–70 mg/ kg body weight | 0.01 mg/kg/day for acute (1–14 days) and intermediate oral exposure (15– 365 days) oral exposure to copper | NIOSH REL TWA 0.1 mg/m3 | [85, 207] | ||
| Iron | Serum ferritin 128.58±13.85 µg% | 4.333 mg/kg body weight for women | - | NIOSH REL TWA 1 mg/m3 | [209, 210] |
||
| Lead | Blood 1.5 μg/dL for adults 20–59 years Urine 0.677 μg/L for ≥ 6 years of age |
For 70 kg adult, 22.0-441.8 mg | No MRLs derived because more sensitive effects have not been established in humans | NIOSH REL TWA (8 hour) 0.050 mg/m3 | [207, 211] | ||
| Manganese | Serum (≥16 years) 0.6-2.3 ng/mL Urine (aged 6–88 years) 1.19 µg/L |
For 70 kg adult, 10 to 20 mg | No MRLs derived interim guidance value 0.16 mg manganese/kg/day |
NIOSH REL TWA 1 mg/m3 | [207, 212] | ||
| Mercury | Blood – below 5 ng/mL Urine – below 20 ng/mL |
In exposed individuals blood 9.8 ± 2.2 µg/L | Chronic inhalation 0.2 µg/m3 for metallic mercury; oral acute 0.007 mg/kg/day and intermediate 0.002 mg/kg/day duration exposures to inorganic mercury |
NIOSH REL TWA (vapour) 0.05 mg/m3 | [207, 213, 214] |
||
| Selenium | Serum 0.125 mg/L | 15 mg in Americans | No MRL was derived for acute exposure 0.005 mg Se/kg/day was derived for chronic oral exposure (≥1 year) low adverse effect level of dietary selenium 1,540–1,600 mg daily |
NIOSH REL TWA 0.2 mg/m3 | [207, 215, 216] | ||
| Zinc | Serum 1 µg/mL Urine 0.5 mg/g creatinine |
For 70 kg adult, 0.66 -2.63 g/kg body weight | 0.3 mg Zn/kg/day for intermediate oral exposure (15–364 days). | NIOSH REL TWA 10 mg/m3 | [207, 211] | ||
| PESTICIDES and INSECTICIDES | |||||||
|
Organochlorine pesticides (OCPs) include hexachlorocyclohexane (lindane, HCH), aldrin, dieldrin, endosulfan, p,p’-dichlorodiphenyl-dichloroethylene (pp’-DDE), o,p’-DDE, p,p’-dichlorodipheny-ltrichloroethane (pp’-DDT), o,p’-DDT, p,p’-dichlorodiphenyl-dichloroethane (p,p’-DDD) and o,p’-DDD |
Serum aldrin 0.004 mg/L and dieldrin 0.002 mg/L in India; serum HCH 0.0182 mg/L; dieldrin 0.0161 mg/L pp′-DDE 1.31 mg/L in unexposed New Zealand adults; serum dieldrin (>12-year-old and older) 0.146 mg/L (whole blood) in USA adults; urine DDT+ DDE 400 µg/L |
Serum dieldrin in farmers 127±27.2 µg/g fat; serum SHCH in farmers 4.3 ± 0.1 ng/g fat; serum SDDT in farmers 7.6 ± 1.7 ng/g fat |
0.002 mg/kg/day for acute exposure to aldrin (≤14 days); 0.00003 mg/kg/day for chronic exposure to aldrin (≥1 year); 0.0001 mg/kg/day for intermediate exposure to dieldrin (15–364 days); 0.00005 mg/kg/day for chronic exposure to dieldrin (≥1 year); acute oral 0.0005 mg/kg/day for DDT; intermediate 0.0005 mg/kg/day for DDT |
NIOSH REL TWA Dieldrin 0.25 mg/m3 [skin]; NIOSH REL TWA HCH, 0.5 mg/m3 [skin]; NIOSH REL TWA Endosulfan 0.1 mg/m3 [skin]; DDT, 0.5 mg/m3 |
[207, 217, 220] | ||
| Organophosphate insecticides (OPIs) including methyl parathion, dimethyl parathion, trichlorfon (TCF), chlorpyrifos (CPF) | No reference values | After exposure, 0.156 mg/L serum methyl parathion | 0.0007 mg/kg/day for intermediate oral exposure (15–364 days) to methyl parathion; 0.0003 mg/kg/day for chronic oral exposure (365 days or more) to methyl parathion |
NIOSH REL TWA 0.05 mg/m3 [skin] for dimethyl parathion | [207] | ||
| Carbamates (e.g., carbofuran) | Urine 28 µg/kg (farmers) | Blood carbofuran 0.4 -18 µg/mL poisoning | Mild effects at 0.1 mg/kg body weight/day | NIOSH REL TWA 0.1 mg/m3 | [221], 223 | ||
| Bipyridyles (paraquat, diquat) | No reference values | Serum 0.4 - 4.0 µg/mL level after paraquat poisoning | Less than 20 mg paraquat ion per kg body weight | NIOSH REL TWA 0.1 mg/m3 (resp) [skin] for paraquat | [224] | ||
| Rotenone | No reference values | Toxicity or poisoning values vary | 40 mg/L drinking water | NIOSH REL TWA 5 mg/m3 | [225] | ||
| Fipronil | No reference values | Toxicity or poisoning values vary | No MRL | Fipronil NOAEL 0.025 mg/kg bw per day; human chronic RfD 300 ng/L/day |
[226] | ||
| Pyrethroids (permethrin deltamethrin) | No reference values | Not evaluated | 0.3 mg/kg/day acute oral exposure to permethrin (≤14 days); 0.2 mg/kg/day intermediate oral exposure to permethrin (15–364 days); no chronic-duration oral MRLs |
EPA exposure limits 0.005-0.05 mg/kg/day | [207] | ||
| Neonicotinoids (acetamiprid, imidacloprid) | No reference values | Due to poisoning plasma acetamiprid 10.58 ng/L; plasma acetamiprid < 44.6 ng/L; plasma imidacloprid 2.3-59.8 mg/L |
Acute dietary acetamiprid exposure 0.039 mg/kg; acetamiprid 600 mg/L (children 1-6 years) |
Acetamiprid NOAEL 10 mg/kg; imidacloprid acute 14 mg/kg/day; RfD 0.057 mg/kg/day | [227, 228] | ||
| OTHER INDUSTRIAL and COMMERCIAL CHEMICALS | |||||||
| Alkylphenol-polyethoxylates (APEOs) including Octylphenol (OP) |
95th percentile 2.2 (1.6–3.2) µg/L | 4-tert-Octylphenol exposed blood serum1.4 ng/g (wet weight) | No MRL | [229] | |||
| Brominated flame retardants (BFRs) including hexabromocyclo-dodecane (HBCD), tetrabromobisphenol-A (TBBPA), decabromodiphenyl ether (DBDE), polybrominated diphenyl ethers (PBDEs) |
Serum congeners BDE-47[geometric mean 20.5 ng/g lipid]; BDE-153 [5.7 ng/g lipid]; BDE-99 [5.0 ng/g lipid; BDE-100 [3.9 ng/g lipid]; BB-153 [2.3 ng/g lipid]; and BDE-28 [1.2 ng/g lipid]. | Breast milk PBDEs 4-419 ng/g lipid PBDE group (BDE-47, 99, 100, 153, 154) 330-2500 ng/kg fat |
0.006 mg/m3 for intermediate inhalation exposure (15–364 days) to lower brominated BDEs; 10 mg/kg/day has derived for intermediate oral exposure (15–364 days) to DBDE |
HBCD NOAEL 14.8 mg/kg-day; TBBPA NOAEL inhalation > 18mg/L; NOAEL oral >100 mg/kg to >2500 mg/kg; pentaPBDE NOAEL 1mg/kg/d |
[207, 236, 230] | ||
| Dioxins (e.g.. 2,3,7,8-Tetrachloro-dibenzo-p-dioxin (TCDD)), Polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), polychlorinated hydrocarbons (PAHs e.g.. naphthalene) | Serum TCDD 2.34 ng/L ( 0.58 – 5.5 ) Serum PCBs 6.2 mg/L |
TCDD body burden 20 ng/L; in individuals 13 years after exposure: serum PCDFs 1,030 ng/kg lipid; serum PCBs 2,220 ng/kg lipid |
0.03 µg/kg/day intermediate oral exposure (15–364 days) to PCBs; 0.02 µg/kg/day chronic oral exposure (365 days or more) to PCBs; No acute, or chronic oral MRLs were derived for PAHs; 0.6 mg/kg/day intermediate oral exposure (15-364 days) to acenaphthene |
NIOSH REL TWA for PCB 0.001 mg/m3 | [207, 237, 238] | ||
| Bisphenol A (BPA) | Serum BPA unexposed 0.276 mg/L Urine BPA unexposed 2000 ug/L |
Serum BPA median 3.198 mg/L | 0.02 µg/kg bw/day minimal health risk to infants and children | NOAEL 5 mg/kg body weight/day | [204, 219, 239, 240] | ||
| Phthalates (monoethyl phthalate (MEP), mono-2-ethylhexyl phthalate (MEHP), monobutyl phthalate (MBP), and monobenzyl phthalate (MBzP), diethylhexyl phthalate (DEHP), di-n-butyl phthalate (DBP), benzylbutyl phthalate (BzBP), and diethyl phthalate (DEP) | In blood; MEP (148000 ng/L), MBP (15100 ng/L), MBzP (7000 ng/L), MEHP (5400 ng/L), and MMP (4500 ng/L); urine DEHP <3.6 µg/kg body weight/day; total phthalates 437.9 ng/mL (8.9-47585 ng/mL) |
- | DEHP 0.1 mg/kg/day for intermediate oral exposure (15–364 days); DEHP 0.06 mg/kg/day was derived for chronic-duration oral exposure (≥365 days) |
DBP NOAEL125 mg/kg/d; BzBP NOAEL159 mg/kg/d; DEP NOAEL 750 mg/kg/d |
[207, 241, 243] | ||
| ANTIMICROBIALS | |||||||
| Parabens (ethyl, benzyl, butyl, methyl, propyl) | Urine methyl paraben: female106- 1,230 male 25.3- 727; urine ethyl paraben: female2.0-138 male <LOD-36.4; urine propyl paraben female 20.2-361 male 2.0-134; butyl paraben female 0.300-31.8 male <LOD-2.70 |
0.03 mg/kg bw/day | No MRL | 0.79, 0.34, and 0.0016 mg/kg bw/day for methyl-, propyl- and butylparaben, respectively | [165, 244, 247] | ||
| Triclosan | Plasma TCS 11 ng/g (age 16–45 years Australians); urine TCS 6.4 mg/L (mg/g creatinine) urine 2.400-3790000 ng/L in USA; blood levels males; 136760 ng/L, females 95380 ng/L in USA |
Urine triclosan concentrations are highest during the third decade of life | No MRL | [248, 250] |
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| Triclocarban | Serum TCC 0.45 ng/mL; urine TCC 3.85 ng/mL |
1% to 5% by body weight | No MRL | - | [159, 162] | ||
| Hexachlorophene (HCP) | Blood 0.02-0.14 mg/L | 0-80 µg/kg adipose tissue | 6 µg/L in drinking water | - | [251] | ||
| AIR POLLUTANTS | |||||||
| Particulate matter (PM) (heavy metals and toxic elements), Ozone (O3) | Sulfate particles (pg/m3) 0.7-7.4 Inhalable PM (pg/m3) 15.4- 32.7 Sulfur dioxide (ppb) 0.2-12.9 Ozone, 24-hr avg. (ppb) 16.3-34.8 Nitric acid (ppb) 0.3-2.1 (l ppb = 40.9 nmol/m3) |
- | Relative risk associated with a 10 µg/m3 change in PM10 | PM2.5, 15.0 μg/m3/ year, 35 μg/m3/24 hours; PM10, 150 μg/m3/24 hours; ozone 0.075 ppm carbon monoxide 9 ppm (10mg/m3)/8 hours; sulfur Dioxide 75 ppb/1 hour; lead 0.15 μg/m3/3 months; nitrogen dioxide 53 ppb/year; 100 ppb/ hour |
[173, 252, 253] | ||
| Volatile Organic Compounds (VOCs, e.g., naphthalene, toluene, xylene) | Blood benzene 0.28 ± 0.34 ng/mL; blood m,p-xylene 0.98 ± 0.93 ng/mL; urine 1,3-butadiene 4.24 ± 12.16 urine benzene 0.75 ± 4.23; urine toluene 0.11 ± 0.14; urine ethylbenzene 0.66 ± 1.17; urine m,p-xylene 0.83 ± 1.18; urine o-xylene 1.22 ± 2.01 |
Benzene 0.009 ppm for acute-duration inhalation exposure (≤14 days); benzene 0.006 ppm for intermediate-duration inhalation exposure (15–364 days); benzene 0.003 ppm for chronic-duration inhalation exposure (≥1 year); xylenes NOAEL 50 ppm; no MRLS for butadiene; toluene acute 1 ppm; chronic 0.08 ppm; ethylbenzene acute 1 ppm, chronic 0.1 ppm |
Benzene NIOSH REL TWA 0.1 ppm; air xylenes NIOSH REL 435 mg/m3; (total xylenes) drinking water 10 mg/L maximum contaminant level; ethylbenzene NIOSH REL TWA 100 ppm | [207, 254] | |||