Risk assessment of chlorinated paraffins in feed and food

Abstract

The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of chlorinated paraffins in feed and food. The data for experimental animals were reviewed and the CONTAM Panel identified the liver, kidney and thyroid as the target organs for the SCCP and MCCP mixtures tested in repeated dose toxicity studies. Decreased pup survival and subcutaneous haematoma/haemorrhage were also identified as critical effects for an MCCP mixture. For the LCCP mixtures tested, the liver was identified as the target organ. The Panel selected as reference points a BMDL ₁₀ of 2.3 mg/kg bw per day for increased incidence of nephritis in male rats, and of 36 mg/kg bw per day for increased relative kidney weights in male and female rats for SCCPs and MCCPs, respectively. For LCCPs, a reference point relevant for humans could not be identified. Due to the limitations in the toxicokinetic and toxicological database, the Panel concluded that derivation of a health-based guidance value was not appropriate. Only limited data on the occurrence of SCCPs and MCCPs in some fish species were submitted to EFSA. No data were submitted for LCCPs. Thus, a robust exposure assessment and consequently a complete risk characterisation could not be performed. A preliminary risk characterisation based only on the consumption of fish was performed, and the calculated margins of exposure suggested no health concern for this limited scenario. The Panel noted that dietary exposure will be higher due to the contribution of CPs from other foods. The Panel was not able to identify reference points for farm animals, horses and companion animals. No occurrence data for feed were submitted to EFSA. Therefore, no risk characterisation could be performed for any of these animal species.

Keywords: LCCP; MCCP; SCCP; chlorinated paraffins; feed; food; risk assessment.

Figure 1

(A) General structure of chlorinated paraffins (CPs) and (B) example of a short‐chain chlorinated paraffin, SCCP (C₁₀H₁₇Cl₅), a medium‐chain chlorinated paraffin, MCCP (C₁₇H₃₁Cl₅) and a long‐chain chlorinated paraffin, LCCP (C₂₀H₃₄Cl₈) of the many possible CP structures

Figure 2

Production of chlorinated paraffins between 1935 and 2012 (from Glϋge et al., 2016, 1)

Figure 3

Arithmetic means of the relative homologue group concentration for short‐chain chlorinated paraffins and medium‐chain chlorinated paraffins in Norwegian, Danish, Scottish and Chilean farmed salmon and in different Eastern Pacific wild salmon (from Krätschmer et al., 2019, 2)

Figure 4

Example of a GC‐ECNI‐Orbitrap‐HRMS chromatogram illustrating the total ion count (TIC, black line) and mass‐to‐charge ratios (m/z, coloured lines) for a few selected short‐chain chlorinated paraffins (SCCPs) and medium‐chain chlorinated paraffins (MCCPs) homologues (Krätschmer, 2019)