Levels of organochlorine contaminants in organic and conventional cheeses and their impact on the health of consumers: an independent study in the Canary Islands (Spain).

In the present work we have evaluated the levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in 61 commercially available brands of cheese (54 conventional and 7 organic) to estimate their relevance as a source of organochlorines. Our results showed that hexachlorobenzene, α-HCH, dieldrin, p,p'-DDE, and PCBs 153 and 180 were present in most of the samples independent of the cheese type. The concentration of OCPs was low for both types of cheese, although organic had lower concentrations than conventional. The estimated daily intake (EDI) of OCPs was lower than the tolerable daily intake (TDI). The levels of PCBs in cheese were also low; however, there were higher levels of PCBs in organic than in conventional brands. Levels of dioxin- like PCBs (DL-PCBs) in both types of cheese reached concentrations in the 75th percentile higher than 3 pg WHO-TEQ/g fat, and above 100% of the levels established by the EU. People consuming the most contaminated brands could have an EDI well above the recommended TDI (2 pg WHO-TEQ/kg bw/day). These results are of concern as the adverse health effects exerted by dioxin-like compounds are well known.