Areas of Localized Organochlorine Contamination in Arizona and New Mexico

Transboundary pollution: Persistent organochlorine pesticides in migrant birds of the Southwestern United States and Mexico

“…Residues of DDE in eggs of cattle egrets collected during 1987 and 1988 at Mexicali averaged 3.2 and 3.5 μg/g ww, respectively, and were higher than in carcasses [43]. Overall, DDE concentrations in birds from northwest Mexico were similar to, and in some cases lower than, those found during the same period in the southwestern United States [14,25–29]. It is important to note, however, that about 40% of the samples had DDE levels above 1 μg/g ww, a level that has been determined as critical, particularly when present in small birds, which are common prey of raptors [7].…”

“…Similarly, nationwide monitoring of organochlorine residues in ducks in the United States indicated that DDE residues were highest (3.3 μg/g ww) in duck wings from Arizona and New Mexico [34]. In 1980 organochlorine residues continued to be high in birds collected in portions of the Gila and Verde Rivers in Arizona [27]. Residues of DDE in duck wings and European starling carcasses from the Verde River averaged 3.12 and 6.44 ppm ww, respectively [27].…”

“…Elevated concentrations of organochlorine pesticides (especially DDE) in birds from the southwestern and western United States were reported throughout the 1970s and 1980s [4,[6][7][8]14,15,[25][26][27][28][29][30][31][32]. Some cases of elevated DDE residues in birds from the southwestern United States have been attributed to local sources resulting from high use of DDT in the past or from impurities in dicofol, an acaricide widely used in the southwest [14,25,26,29].…”

“…In 1980 organochlorine residues continued to be high in birds collected in portions of the Gila and Verde Rivers in Arizona [27]. Residues of DDE in duck wings and European starling carcasses from the Verde River averaged 3.12 and 6.44 ppm ww, respectively [27]. Furthermore, ducks collected in 1982 from New Mexico and Arizona continued to have elevated DDT and DDE residues that were attributed to local contamination rather than to accumulation on wintering grounds [14].…”

Detailed study of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1988-90

“…Since 1988, DDT also has been regulated in dicofol (now required to contain less than 0.1 percent DDT). Recent concentrations of p,p'-DDE, a metabolite of DDT, found in resident fauna in the Southwestern United States (including Texas, New Mexico, Arizona, and the Salton Sea area) were at levels associated with eggshell thinning and reduced reproductive success in birds (Clark and Krynitsky, 1983;Fleming and Cain, 1985;White and Krynitsky, 1986;Ohlendorf and Marois, 1990). Clark and Krynitsky (1983) and White and others (1983) have suggested that recent use of DDT may have occurred in the Southwest; however, others (1985, 1990) found no evidence of such use on the basis of fish data for the region.…”