Impact of Long-Term Weathering, Mobility, and Land Use on Chlordane Residues in Soil

Abstract

The use of technical chlordane, a mixture of 147 separate components, and chlordane-containing products has been illegal in the United States since 1988. Technical chlordane is a member of the persistent organic pollutants (POPs), all of which exhibit remarkably long half-lives in the environment. Due to its persistence, its former use at extremely high application rates, and its toxicity, technical chlordane in soil may be present at levels of concern to public health. Concentrations at a site for which the date and rate of application of technical chlordane were recorded permit an accurate description of its weathering and an assessment of its vertical and horizontal movement during the past several decades. This site also allows computation of half-life as an average across the 147 components in soil 38 years after application using explicitly stated assumptions. Levels of technical chlordane in soils spanning a variety of land uses including agricultural sites, residential lawns and gardens, and foundation sites are also presented.

Inheritance Profile of Weathered Chlordane andP,P′-DDTs Accumulation bycucurbita pepohybrids

“…This wide variation in contamination for both POPs was expected; however, for a given mound, variability among the triplicate soil extractions was less than 5% for chlordane and less than 10% for DDX. These levels of chlordane are in agreement with previous findings (Mattina et al 1999 and the DDX concentrations are indicative of historical contamination with DDT (White 2001;White et al 2007). For chlordane, the component ratios (CR) for TN, TC, and CC were 0.21 (±0.02), 0.32 (±0.02), and 0.46 (±0.02), respectively.…”

“…The plot (approximately 12m × 21m) was treated with technical chlordane in the 1960s and was subsequently under turf until 1998, when the area was turned over for periodic experimentation. Chlordane residues ranging from 1-18 μg/g have been reported in this soil (6.5% organic matter) (Mattina et al 1999;Eitzer et al 2001). Anecdotal study of this site has also confirmed the presence of p,p -DDT, as well as the metabolites p,p -DDD and p,p -DDE, at concentrations of 50-300 ng/g.…”

“…Although the use of chlordane and DDT in the United States was discontinued 25-40 years ago, soils and sediments contaminated with low to moderate levels of these pollutants are ubiquitous (Mattina et al 1999;Wong and Bidleman 2011). The persistence of these chemicals in the environment is in part due to synthetic molecular structure; with no natural analogs present, degradative pathways have not evolved.…”

Factors affecting the phytoaccumulation of weathered, soil-borne organic contaminants: analyses at the ex Planta and in Planta sides of the plant root

“…Sequestration or irreversible adsorption of POPs in the soil matrix over time (Hawthorne and Miller 2003) was also assumed to reduce their bioavailability to soil microbes, fauna such as earthworms (Morrison et al 2000) and, by extension, to flora. Consequently, half-lives of the chemicals in soils range from years (Handbook of Environmental Degradation Rate 1991), to decades (Mattina et al 1999) and even centuries (Kurt-Karakus et al 2006).…”

Comparative effects of rootstock and scion on dieldrin and endrin uptake by grafted cucumber (Cucumis sativus)

“…Organochlorine pesticides such as DDT, chlordane, mirex, heptachlor, hexachlorobenzene, toxaphene, and the drins categorized as POPs were banned for use on crops in most developed countries by 1990 3) ; however, because of their long persistence, these compounds are still found in soils. [4][5][6][7] The halflives of dieldrin and endrin in soils are relatively long (5-12 years). 8) Therefore, the risk of drin residues being present in crops cultivated in polluted soils might continue for years or decades.…”