Jerrold Forester

Effects of Aroclor(R) 1254 on Laboratory-Reared Embryos and Fry of Sheepshead Minnows (Cyprinodon variegatus)

Abstract Eggs of the sheepshead minnow (Cyprinodon variegatus) were artificially fertilized and maintained at temperatures from 15 to 35 C and in salinities from 0 to 35‰ to determine efficient culture conditions. Fertilization was not affected by temperature or salinity ranges chosen, but hatching success was greatest (x2; α = 0.01) at a temperature range of 24 to 35 C and a salinity range of 15 to 30‰. Artificially fertilized sheepshead minnow eggs were exposed to logarithmic concentrations of Aroclor 1254 (10.0 to 0.1 μg/liter) in seawater averaging 30 C and 24‰ in a flow-through bioassay. Fertilization was not affected but significantly fewer embryos developed in the 10.0 μg/liter concentration, and fewer fry survived in concentrations greater than 0.1 μg/liter. Fry were more susceptible to Aroclor 1254 than were embryos, juveniles, or adults.

Effects of the polychlorinated biphenyl Aroclor® 1254 on the American oyster Crassostrea virginica

Young oysters (Crassostrea virginica) were continuously exposed to Aroclor® 1254, a polychlorinated biphenyl (PCB), in flowing, unfiltered seawater. Growth rate (height and in-water weight) was significantly reduced (α=0.05) in oysters exposed to 5 μg/l (ppb) for 24 weeks. Growth rate was not affected in oysters exposed to 1 ppb for 30 weeks. Mortality was not significant in exposed and control groups. In oysters exposed to 5 ppb, greatest PCB residue (whole body) was 425 mg/kg (ppm), 85,000x the concentration in the water, and less than 0.3 ppm was retained after 28 weeks depuration in PCB-free water. In oysters exposed to 1 ppb, greatest residue was 101 ppm, 101,000x the concentration in the water, and less than 0.2 ppm was retained after 12 weeks depuration. Examination of oysters exposed to 5 ppb of this PCB for pathogenesis revealed atrophy of digestive diverticular epithelium and degeneration of vesicular connective tissues concomitant with leukocytic infiltration, but tissue recovery seemed excellent after 12 weeks depuration.

Aroclor 1016: Toxicity to and uptake by estuarine animals

Abstract Bioassays were conducted to determine the acute toxicities of the polychlorinated biphenyl (PCB) Aroclor 1016 in flowing sea water to American oysters ( Crassostrea virginica ), brown shrimp ( Penaeus aztecus ), grass shrimp ( Palaemonetes pugio ), and pinfish ( Lagodon rhomboides ), and to determine its chronic toxicity to, and uptake and retention by pinfish. Acute 96-hour EC50s or LC50s were: oysters, 10.2 μ/liter; brown shrimp, 10.5 μg/liter; grass shrimp, 12.5 μg/liter. The PCB was not toxic to pinfish at 100 μg/liter for 96 hours, but significant mortality occurred when pinfish were exposed to 32 μg/liter of Aroclor 1016 for 42 days. Pinfish exposed to 1 μg/liter for 56 days accumulated the chemical with maximum concentrations attained in whole-fish by 21 to 28 days. Maximum whole-body residue (wet weight) was 17,000 × the nominal concentration in test water. Tissue alterations, such as severe vacuolation in the pancreatic exocrine tissue surrounding the portal veins, occurred in pinfish exposed to 32 μg/liter of Aroclor 1016 for 42 days.

Chlordane: Effects on several estuarine organisms

Dynamic marine toxicity tests were performed with technical grade chlordan and eastern oysters (Crassostrea virginica), pink shrimp (Penaeus duorarum), grass shrimp (Palaemonetes pugio), sheepshead minnows (Cyprinodon variegatus), and pinfish (Lagodon rhomboides). The 96-hr LC20S (and 95% confidence limits) based on measured concentrations of chlordane (in mug/liter) are: ping shrimp 0.4 (0.3-0.6); grass shrimp, 4.8 (4.0-6.0); sheepshead minnows, 24.5 (19.9-28.6); and pinfish, 6.4 (5.0-7.3). The 96-hr EC50 for eastern oysters was 6.2 (4.8-7.9). In a flow-through test, embryos and fry of sheepshead minnows were exposed to average measured concentrations of chlordane from 1.3 to 36.0 mug/liter for 28 days. Neither fertilization success nor embryo survival was affected by the concentrations of chlordane to which these life stages were exposed. However, sheepshead minnow fry did not survive for more than 10 days in chlordane concentrations greater than 7.1 mug/liter.

Toxicity and bioconcentration of BHC and lindane in selected estuarine animals

Flow-through, 96-hr bioassays were conducted to determine the acute toxicity of technical BHC and lindane to several estuarine animals. Test animals and their respective 96-hr lindane LC50 values were: mysid(Mysidopsis bahia), 6.3 µg/L; pink shrimp(Penaeus duorarum), 0.17 µg/L; grass shrimp(Palaemonetes pugio), 4.4 µg/L; sheepshead minnow(Cyprinodon variegatus), 104 µg/L; and pinfish(Lagodon rhomboides), 30.6 µg/L. The 96-hr LC50 values for pink shrimp and pinfish exposed to BHC were 0.34 and 86.4 µg/L, respectively.Two BHC bioconcentration studies were conducted with the oyster,Crassostrea virginica, and pinfish. After 28 days exposure, oysters bioconcentrated an average of 218 X the BHC measured in exposure water, while pinfish bioconcentrated 130 X in their edible tissues and 617 X in offal. After one week in BHC-free sea water, no detectable residues were measured in oysters or pinfish.

Heptachlor: Toxicity to and uptake by several estuarine organisms

Technical-grade heptachlor (65% heptachlor, 22% trans-chlordane, 2% cis-chlordane, and 2% nonachlor) was tested in 96-hr bioassays to determine its toxicity to estuarine animals. The test organisms and the 96-hr LC50 or EC50s based on measured concentrations in water) are as follows: American oyster (Crassostrea virginica), 1.5 mug/liter; pink shrimp (Penaeus duorarum), 0.11 mug/liter; grass shrimp (Palaemonetes vulgaris), 1.06 mug/liter; sheepshead minnow (Cyprinodon variegatus), 3.68 mug/liter; pinfish (Lagodon rhomboides), 3.77 mug/liter; and spot (Leiostomus xanthurus), 0.85 mug/liter. Analytical-grade heptachlor (99.8% heptachlor) and heptachlor epoxide (99%) were also studied. The analytical-grade heptachlor 96-hr LC50 for pink shrimp and spot was 0.03 mug/liter and 0.86 mug/liter, respectively, while that for pink shrimp exposed to heptachlor epoxide was 0.04 mug/liter. Heptachlor was accumulated and some metabolized to its epoxide by all animals tested. Fish and oysters accumulated heptachlor in their tissues 2,800-21,300 times the measured concentration in water; shrimp, only 200-700 times.

Uptake and toxicity of toxaphene in several estuarine organisms.

The organochlorine insecticide, toxaphene, was tested in flow-through bioassays to evaluate its toxicity to estuarine organisms. The organisms tested and their respective 96-hr LC5Os (based on measured concentrations) are: pink shrimp (Penaeus duorarum), 1.4Μg/L; grass shrimp (Palaemonetes pugio), 4.4Μg/L; sheepshead minnow (Cyprinodon variegatus), 1.1Μg/L; and pinfish (Lagodon rhomboides), 0.5Μg/L. Toxaphene concentration estimated to reduce shell deposition in American oysters (Crassostrea virginica) by 50% (EC50) was 16Μg/L. Concentration factors (concentration of toxaphene in tissues divided by concentration measured in water) for fishes and oysters in 96 hr ranged from 3,100 to 20,600 and for shrimp, from 400 to 1,200.Individuals from various ontogenetic stages of longnose killifish (Fundulus similis) were exposed to toxaphene for 28 days in flow-through bioassays. Toxaphene was toxic to embryos, fry, juveniles, and adult fish, but fertilization of ova in static tests was not affected by the concentrations tested (0.32 to 10Μg/L). The 28-day measured LC50s for all stages ranged from 0.9 to 1.4Μg/L. Toxaphene was accumulated in ova and other body tissues of the longnose killifish; concentration factors in ova were 1,000 to 5,500, and in whole-body tissues, 4,200 to 60,000.

Effects of Aroclor(R) 1016 on Embryos, Fry, Juveniles, and Adults of Sheepshead Minnows (Cyprinodon variegatus)

Abstract We investigated the toxicity of Aroclor 1016 to, and uptake by, fry and juvenile and adult sheepshead minnows (Cyprinodon variegatus) in intermittent-flow bioassays lasting 28 days. Survival of eggs, of fry hatched from them, and of juvenile and adult fish apparently was not affected by 0.1, 0.32, 1.0, 3.2, or μg/liter of Aroclor 1016 added to aquaria, but 32 and 100 μg/liter killed newly hatched fry and juvenile and adult fish. Sheepshead minnows accumulated the chemical in proportion to its concentration in the test water. Fry contained 2,500 to 8,100 X the concentration of Aroclor 1016 added to the test water, adults 4,700 to 14,000 X, and juveniles 10,000 to 34,000 X. As much as 77 μg/g of Aroclor 1016 in eggs from exposed adults apparently did not affect survival of embryos and fry.

Mirex and marine unicellular algae: Accumulation, population growth and oxygen evolution

Many organochlorine compounds are toxic to algae. SODERGREN (1967) demonstrated that less than 0.3 parts per billion (ppb) of DDT inhibited growth of a fresh water species of Chlorella. WURSTER (1968) reported that DDT reduced the rate of photosynthesis in five species of marine algae, de la CRUZ and NAQVI (1973) showed that one part per million (ppm) of mirex reduced net photosynthesis by 55% in a fresh water species of Chlamydomonas.

Translocation of four organochlorine compounds by red mangrove (Rhizophora mangle l.) seedlings

SummaryMangrove seedlings from the field were found to contain DDD, dieldrin, and PCBs.In the laboratory, mangrove seedlings translocated dieldrin, methoxychlor, mirex, and Aroclor 1242 (a PCB) from soil to various plant parts. Dieldrin was detected in hypocotyls and leaves of seedlings exposed to application rates of 0.06 kg/ha and above; methoxychlor in hypocotyls at rates of 0.28 kg/ha and above; Aroclor 1242 in hypocotyls and leaves at rates of 0.56 kg/ha and above; and mirex in roots, hypocotyls, stems, and leaves only at the highest treatment rate of 11.20 kg/ha.The data show that these persistent organochlorine compounds can be translocated to seedlings. If the compounds are present in the natural mangrove environment, it is possible that they could enter seedlings and pass to higher trophic levels when seedlings are eaten by estuarine organisms.