Are historical sheep dipping baths in the Ribble Valley a source of arsenic pollution able to cause significant harm to human health?

Abstract

The historical use of the carcinogen arsenic as a pesticide for the protection of livestock caused many human health problems during its worldwide use from its inception in the 19th century to its decline in use from the 1950’s. Due to the resilience of arsenic trioxide (As2O3) this inorganic compound remains present in soil at historical sheep dipping baths and is still a threat to human health today. The primary aim of this study was to establish the arsenic levels of the soils surrounding the historical sheep dipping, and secondly to assess the potential for harm to human health through possible pollution to receptor pathways. Using historical maps to identify potential farms and following a preliminary questionnaire to ascertain each sites suitability for the research purposes, a suitable sheep dipping site was selected in the area of interest in Dilworth, Lancashire. Multiple soil samples were extracted at specified depths and distances from the sheep dipping bath to determine both the spread of arsenic at distance from the site and through the soil horizon. Elevated total arsenic levels of 1371.2 mg/kg were found in the soil. A significant difference between the contaminated site and the control site was observed at p < 0.05. The high levels of arsenic observed in this study are a source of concern for human health. The lack of current concern in this country over this subject matter necessitates further study into the human health implications of these historical sheep dipping baths nationwide.