Table 7.
Previous assessments on long‐chain chlorinated paraffins (C18–26)
| Organisation | TDI (μg/kg bw per day) | NOAEL (mg/kg bw per day) | Critical endpoint(s) | Relevant study | Study reference | Uncertainty factor | Remarks |
|---|---|---|---|---|---|---|---|
| WHO/IPCS (1996) | 100 | 100 (LOAEL) | Multifocal granulomatous hepatitis and increased liver weight in female rats | 2‐year rat study | NTP (1986b); Serrone et al. (1987); Bucher et al. (1987) | 1,000 | Uncertainty factor for intra‐ and interspecies variations (10 × 10), and an additional factor of 10 for LOAEL instead of NOAEL |
| NRC (2000) | 300 (RfD) | 900 |
C22–26, 70% chlorination: liver toxicity (↑ relative liver weight, hepatocellular hypertrophy, cytoplasmic fat vacuolation, ↑ in serum ALT and AST activities) and kidney toxicity (a slight ↑ in the incidence of nephritis in males) |
90‐day rat study | Serrone et al. (1987) | 3,000 | A factor of 3 (instead of 10) for interspecies variation because toxicokinetics and dynamics of LCCPs were anticipated to be similar in rodents and humans, a factor of 10 for intraspecies variation, a factor of 10 to account for less‐than‐lifetime toxicity data, a factor of 10 because the toxicity database for the LCCPs (C22–26, 70% chlorination) was incomplete |
| Health Canada (2008, 2012) | 71 | 100 (LOAEL) | Diffuse lymphohistiocytic inflammation in the liver and in the pancreatic and mesenteric lymph nodes in female rats | 2‐year rat study | NTP (1986b) | 1,000 | Uncertainty factor for intra‐ and interspecies variations (10 × 10), an additional factor of 10 for LOAEL instead of NOAEL and a factor 5/7 for conversion of 5 days/week administration to daily exposure |
| UK‐Environment Agency (2009) | Not derived |
C22–26, 43% chlorination: 100 (LOAEL) C23, 43% chlorination: 100 (LOAEL) C20–26, 70% chlorination: 900 (NOAEL) C18–20: 23 (NOAEL), based on read‐across from MCCP |
Liver changes in females at all treatment levels Microscopic changes in the liver and lymph nodes Effects on body weight gain, food consumption and the liver |
90‐day rat study 2‐year rat study 90‐day rat study |
IRDC (1984)a NTP (2016) IUCLID (2003) |
n.a. | For the risk characterisation, it was suggested to divide the LOAEL by 3 to provide an estimate of the NOAEL |
| US‐EPA (2015) | Not derived | 100 (LOAEL) | Granulomatous inflammation of the liver in female rats | 2‐year rat study | NTP (1986b) | n.a. |
ALT: alanine aminotransferase; AST: aspartate aminotransferase; NOAEL: no‐observed adverse effect level; LOAEL: lowest‐observed adverse effect level; TDI: tolerable daily intake; bw: body weight.
IRDC, 1984. Chlorinated paraffin: 43 per cent chlorination of long‐chain length n‐paraffins. 13‐week day oral toxicity study in rats, with combined excretion, tissue level and elimination study. IRDC report 438‐028/438‐021. As cited in UK‐Environment Agency (2009). Note: Study report also provided to EFSA (IRDC, 1984d, see Documentation provided to EFSA).