Photo Credit: Steve Slater

A new study published in Environmental Pollution has found that the iSimangaliso Wetland Park, a World Heritage site in South Africa, is contaminated with organochlorine pesticides (OCPs). Researchers quantified OCPs from sediment samples from Lake St Lucia, Mkhuze, Lake Sibaya and Kosi Bay. They found high levels of HCH, DDT, endosulfan and heptachlor in the sediments. DDT (in the form of its breakdown products) was most likely due to past mosquito control. Endosulfan and heptachlor concentrations were likely the result of agricultural activities. The measured levels of OCPs represent some of the highest reported contamination levels worldwide. Researchers noted that the retention of large quantities of OCPs in wetlands likely will have adverse impacts on both the ecological environment and human health.