EFFECTS OF INSECTICIDE USE IN A PINE SEED ORCHARD ON PESTICIDE LEVELS IN FISH¹

Abstract

A hydroelectric lake on the Oconee River in central Georgia was sampled on a quarterly basis for four years to determine the impact of three insecticides on the pesticide loading of fish. The insecticides carbofuran (2,3,‐dihydro‐2,2‐dimethyl‐7‐benzofuranyl methyl‐carbamate), fenvalerate [cyano(3‐phenoxyphenyl)methyl 4‐chloro alpha (1‐methylethyl)benzeneacetate], and azinphosmethyl [0,0‐Dimethyl S‐(4‐oxo‐1,2,3‐benzotriazin‐3‐(4H)‐ylmethyl phosphorodithioate] were used to control cone and seed insects on a pine seed orchard that is adjacent to Lake Oconee. Fish populations in areas of the lake that receive runoff from treated and untreated portions of the seed orchard were sampled using gill nets. Water and fish samples were collected monthly in 1981–1983 and quarterly in 1984. Species collected included carp (Cyprinus carpio), sucker (Catostomus spp., Erimyzon spp., Moxostoma spp., Minytrema spp.), bass (Micropterus spp.), channel catfish (Ictalurus punctatus), spotted gar (Lepisosteus spp.), and bluegill sunfish (Lepomis macrochirus). Few carbofuran residues (< 7 percent of fish samples contained detectable residues) and no azinphosmethyl or fenvalerate residues were detected despite measured inputs into the lake after insecticide application. Persistent agricultural insecticides including dieldrin, lindane, DDT, and toxaphene were detected in 32, 36, 58, and 83 percent of sampled fish, respectively. Screening for 20 other insecticides resulted in no detection of residues at a detection limit of 30–100 μg kg‐1.

Assessing the potential for pesticide leaching for the pine forest areas of Tenerife

“…Toxicol. Carbofuran, which is currently applied in Tenerife to control nematode populations [23,24,26], has also been detected in [37], with impacts on nontarget organisms being reported [5]. 20,2001 R. Diaz-Diaz and K. Loague Table 4.…”

“…Much of the information that was available 20 years ago came from studies performed in coastal areas of the northwestern United States [3]. Terrestrial invertebrate populations were impacted by applications of hexazinone (3cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4-(1H,3H)-dione) [4], and fish populations were impacted by applications of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl-n-methylcarbamate) [5]. Direct impacts of pesticide use in forest ecosystems on nontarget organisms have also been reported.…”

Use of gleams to predict insecticide losses from pine seed orchards

“…To assess insecticide runoff risks, the LC50 concentration for a target fish species has been used as a benchmark in several studies [19,20]. The bluegill (Lepomis macrochirus) 96-h LC50 was selected for toxicity evaluation of each insecticide.…”

“…The bluegill (Lepomis macrochirus) 96-h LC50 was selected for toxicity evaluation of each insecticide. Bluegills were used because the fish is common throughout the region and toxicity data are readily available [ 19,211. The predicted contractions were for peak stormflow concentrations that were usually less than several hours in duration.…”

Assessing the Potential for Pesticide Leaching for the Pine Forest Areas of Tenerife

“…Direct impacts of pesticide use in forest ecosystems on nontarget organisms have also been reported. Terrestrial invertebrate populations were impacted by applications of hexazinone (3cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4-(1H,3H)-dione) [4], and fish populations were impacted by applications of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl-n-methylcarbamate) [5]. To our knowledge, the assessment of potential groundwater contamination resulting from pesticide applications in forested areas has not been previously reported.…”