Global prevalence and health risk assessment of organochlorine pesticide residues in raw cow's milk: A systematic review

Milk is a nutrient-rich food essential for human health, yet contamination with organochlorine pesticides (OCPs) poses serious public health risks due to their toxicity and bioaccumulation potential. This systematic review analyzed 41 studies from the past decade, covering 3870 raw cow's milk samples from 66 regions across 17 countries, including 15 developing and 2 developed nations. Analytical methods such as GC-ECD and GC-MS detected 22 OCPs, with DDTs, endosulfan, HCH isomers, and drins being the most prevalent. DDT and its derivatives were found at the highest levels, particularly in Sudan (2180 ng/g), exceeding maximum residue limits (MRLs). Elevated residues of endosulfan (455 ng/kg in Sahiwal, Pakistan), HCH (926 ng/kg in Paliakalan, India), drins (in Punjab, Pakistan, and Giza, Egypt), and heptachlor (notably in Egypt and Nigeria) were also reported. Health risk assessments revealed hazard quotient (HQ) values above 1 for drins in Alexandria Province and Giza, Egypt, and for heptachlor in Giza, with cumulative hazard index (HI) indicating moderate to high non-carcinogenic risks in Punjab, Pakistan, and multiple Egyptian regions. These findings highlight spatial and seasonal variability in OCP contamination and underscore the need for stricter pesticide regulation, routine milk monitoring, and sustainable pest management practices to protect public health.