A Preliminary Human Health Risk Assessment of Organochlorine Pesticide Residues Associated with Aquatic Organisms from the Rangsit Agricultural Area, Central Thailand

ABSTRACT

Food consumption is one of the main routes of human exposure to organochlorine pesticide residues (OCPRs). To assess the potential health risks associated with OCPRs contaminants due to freshwater organism consumption, a number of vegetables, prawn, snail, and fish were collected from Khlong 7 (canal), Rangsit agricultural area, Pathum-Thani Province, Thailand. The samples were extracted using a multiresidue extraction method and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb) levels. Based on a plausible worst-case scenario, the local population could be at risk for cancer due to consumption of fish contaminated by α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, dieldrin, DDD, DDE, and DDT. Likewise, individuals may be at risk from consumption of Lanchester's freshwater prawn Macrobrachium lanchesteri, freshwater snail Filopaludina mertensi, swamp morning-glory Ipomomea aquatica, neptunia Neptunia oleracea, and water lily Nymphaea lotus because these species all contained elevated concentrations of α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, and dieldrin.

Key Words:

• food consumption
• human health risk assessment
• organochlorine pesticides

ACKNOWLEDGMENTS

This research was supported by the National Research Center for Environmental and Hazardous Waste Management (NRC-EHWM), Chulalongkorn University. Particularly, we greatly thank Saran Kiethmaleesatti for field assistance. Support was also provided from the Thai Fogarty ITREOH Center D43 TW007849-01 NIH Fogarty International Center and NIEHS P30ES05022.

Notes

^a Oral reference dose and

^b Cancer slope factor were obtained from USEPA's Integrated Risk Information System (IRIS), www.epa.gov/iris/

^a Identification keys are from Nelson (1976), Rainboth, (1996), Monkolprasit et al. (1997), Suwannakul and Suwannakearnikom (2001), Vidthayanon (2002), and Vidthayanon (2004);

^b Source: Nutrition Division (1995);

^c local name.