Nationwide residues of organochlorines in wings of adult mallards and black ducks, 1972-73.

Organochlorine residues in wings of adult mallards and black ducks were monitored during the 1972-73 hunting season. DDE, DDT, DDD, dieldrin, and polychlorinated biphenyls (PCB's) were present in all samples. Mallard wings from Alabama contained the highest mean levels of DDE, DDT, DDD, dieldrin, and PCB's. Mallards and black ducks from the Atlantic Flyway and mallards from the Pacific Flyway contained significantly lower DDE residues than in 1969-70. Black ducks from the Atlantic Flyway contained significantly less dieldrin than in 1969-70, and mallards in the Central and Pacific Flyways contained significantly lower levels of PCB's. As in 1969-70, DDE residues were lowest in the Central Flyway and highest in the Atlantic Flyway. The average PCB level remained unchanged in the Atlantic Flyway but was higher in the Mississippi Flyway than in 1969-70, probably because of the unusually high levels in Alabama samples. All organochlorine residues in black ducks from the Atlantic Flyway significantly correlated. DDE concentrations in mallards from the Atlantic Flyway significantly correlated with those of DDT, DDD, and PCB's.     

Mercury residues in breast muscle of wild ducks, 1970-71.

Samples of breast muscle from 327 ducks collected from October 1970 to March 1971 in the conterminous United States were analyzed for total mercury by flameless atomic absorption spectrometry. Mercury levels for the entire collection ranged from less than 0.01 to 3.91 ppm wet weight with a median of 0.10 ppm. Twenty-five ducks had levels equalling or exceeding the 0.5 ppm guideline for fish and shellfish established by the Food and Drug Administration, U.S. Department of Health, Education, and Welfare. Dabbling ducks, which are shallow-water feeders and mostly vegetarian in fall, winter, and spring, usually had lower levels than diving and sea ducks. Levels were generally higher in ducks collected in areas where environmental mercury levels were known to be greater than in ducks from nonsuspect areas. Despite the mobility of the ducks, levels seemed more closely linked to local environmental contamination than to various factors associated with large geographic areas.     

Insecticide residues in the Tuttle Creek Reservoir Ecosystem, Kansas-1970-71.

Various components of the aquatic ecosystem of Tuttle Creek Reservoir on the Big Blue River in northeastern Kansas were examined for organochlorine insecticide residues in 1970-71. Components examined were water, sediments, periphyton, zooplankton, insects, and whole-body samples of 10 common fish species. Only dieldrin and sigmaDDT residues were detected. Dieldrin was found in part of the nonfish samples at levels ranging up to 0.01 ppm and in 97 percent of the fish samples with a high level of 0.17 ppm. SigmaDDT residues were also detected in part of the nonfish samples at levels ranging up to 0.42 ppm, and in 98 percent of the fish samples at levels as high as 0.57 ppm. Authors' findings are roughly similar to those of other surveys of Kansas fishes. All levels are relatively low compared with those reported in surveys from other parts of the Nation.     

Organochlorine insecticide residues in bovine milk and manufactured milk products in Illinois, 1971-76.

Monitoring activities were initiated in 1971 to survey the occurence and levels of organochlorine insecticide residues in bovine milk and manufactured milk products in Illinois. Dieldrin residues were the most prevalent, and were found in 96 percent of the samples. Dieldrin also accounted for the highest average residue concentration (0.09 ppm). Only 0.3% of the samples contained illegal insecticide residues. Levels of DDT and lindane were generally declining, but those for dieldrin and heptachlor epoxide tended to remain constant.     

Organochlorine residues in fish: National Pesticide Monitoring Program, 1970-74

As part of the National Pesticide Monitoring Program, the U.S. Fish and Wildlife Service analyzed organochlorine contaminant residues in fish samples collected from about 100 stations each year from 1970 to 1974. During this period, mean residues of DDT and its metabolites declined nationally but remained widespread, and high concentrations continued to be present in areas where DDT use was extensive. Results of interlaboratory crosscheck analyses supported these conclusions, despite interpretation problems posed by intercompound analytical interferences in 1970 and 1971. Temporal trends in PCB residues were less obvious. Highest PCB residues were found in the industrialized areas of the Northwest and Midwest, and traces were present at most stations. Dieldrin and endrin residues remained essentially unchanged during this period; dieldrin residues were widespread and were highest in Hawaii and in areas of the Midwest where aldrin was used extensively. Toxaphene occurrence increased; it was formerly found only in fish from streams draining cotton-farming regions, but residues were detected in 1974 samples from other areas. According to the recommendation of the National Academy of Sciences' Water Quality Criteria, organochlorine residues in freshwater fish may have represented a hazard to piscivorous fish and wildlife at 71 percent of the stations sampled in 1970 and 66 percent in 1974.     

Dieldrin, DDT, PCBs, and mercury levels in freshwater mullet from the upper Great Lakes, 1975-76.

Freshwater mullet harvested commercially during various seasons of 1975-76 from the upper Great Lakes were analyzed for organochlorine pesticides, PCBs, and mercury. Species analyzed were Catostomus commersoni, C. catostomus, and Moxostoma erythruran. Whole ground fish, mechanically deboned flesh, head, middle, and tail steaks, and various muscles were analyzed for pesticides and PCBs; only edible flesh was analyzed for mercury. Dieldrin ranged from none detected to 0.23 ppm in deboned and whole ground samples, the DDT range was a trace to 0.30 ppm, and PCBs ranged from 0.06 ppm to 0.79 ppm. Levels were also higher in head sections and in high fat-containing medial muscle and belly flap. Mercury levels ranged from 0.03 ppm to 0.28 ppm in the flesh of mullet from Lake Michigan.     

Pesticide and mercury residues in commercially grown catfish.

In 1970, 54 commercial catfish farms in Arkansas and Mississippi were sampled for pesticide and mercury residues. Pesticide residues above FDA action levels were detected in 15 percent of the fish samples. Data on residues in sediment, fish feed, and source water suggest that fish were not being contaminated from these sources. Average fish residue per county was, however, strongly correlated with the percent of total acres planted in cotton and soybeans. Results strongly suggest that cotton production was the primary source of contamination. Actual routes of movement have not been clearly defined but aerial transport seems most probable.     

Organochlorine pesticide residues in soils from six U.S. Air Force bases, 1975--76.

Soil samples collected during 1975 and 1976 from United States Air Force installations in California, Georgia, Ohio, Oklahoma, Texas, and Utah were analyzed for organochlorine pesticide residues. Sigma DDT, chlordane, and dieldrin were the pesticides most commonly found. In 1975, sigma DDT residues were significantly higher in samples from residential areas than in samples from golf courses or areas free of pesticide application. Chlordane residues in 1975 were significantly higher in both residential and golf course areas than in areas where pesticides had not been used. No significant differences were found in 1976 in residue levels of any pesticide monitored among various land use areas.     

Mirex residues in bobwhite quail after aerial application of bait for fire ant control, South Carolina--1975-76

Mirex, the organochlorine compound used for control of the imported fire ant (Solenopsis invicta Buren), was applied aerially under supervision of the South Carolina Plant Pest Regulatory Service in October 1975 to a game management area in Hampton County, S.C. Influenced by recent reports indicating that low levels of mirex were toxic to certain nontarget organisms in laboratory studies, authors initiated a program for monitoring mirex residues in bobwhite quail (Colinus virginianus). Pretreatment residues were recorded on a dry-weight basis in bobwhite quail breast and adipose tissue; conversion factors for determining wet-weight concentrations are approximately as follows: fat, 0.77; and breast, 0.29. Residues ranged from 0.000-0.178 ppm and 0.247-2.763 ppm, respectively. Mirex residues in quail adipose tissue showed up to five-fold increase within the first month after treatment and declined thereafter. A residue peak was noticed the spring following mirex treatment, corresponding with insect emergence. Mirex residues in quail collected in summer 1976 following a fall bait application showed slightly higher residue levels than had birds taken in summer 1975; however, little, if any, human food chain contamination would result in the consumption of birds with residue levels found in this study.     

Pesticide residues in the total diet in Canada. IV. 1972 and 1973

Foods, representing an average Canadian diet, were prepared for eating, made into homogenised composites, each containing one type of produce, and analysed for pesticide residues and arsenic. The amounts found were at a consistently low level which could contribute approximately 20 μg total pesticide residues and 35 μg arsenic/person/day.