Matthew J. Zabik

Chlorine and ozone washes for pesticide removal from apples and processed apple sauce

Abstract The effectiveness of chlorinated and ozonated water dips in the dissipation of azinphos-methyl, captan and formetanate hydrochloride in solution and on fresh and processed apples was examined. All three pesticides in model systems solution decreased 50–100% with chlorine and ozone treatment. Captan and formetanate-HCl were both rapidly degraded in 50 and 500 mg liter −1 chlorine solutions at pH 7 and 10.7. Ozonation was also effective in degrading the pesticides. Rate of degradation of the pesticides generally increased at higher pH and temperature. Pesticide residues on fresh apples and in processed products were also reduced by chlorine and ozone washes; chlorine (500 mg liter −1 ) being the most effective wash treatment. Ozone wash at 0.25 mg liter −1 was not as effective owing to its low concentration, its instability in water and the high organic content of the wash water.

Pesticide residues, PCBs and PAHs in baked, charbroiled, salt boiled and smoked Great Lakes lake trout

Abstract Skin-off lean lake trout (Salvelinus namaycush namaycush) from Lakes Huron, Michigan and Ontario as well as siscowets (fat lake trout) (Salvelinus namaycush siscowet) from Lake Superior were cooked by baking and charbroiling to determine the potential of processing/cooking on reducing the levels of pesticides and total PCBs in fish at the dinner table. Lake trout from Lakes Michigan and Superior also were salt boiled and skin-on fillets smoked. All fish analyzed were below the action level except skin-on siscowets with > 0.3 ppm action level for chlordane. Cooked lake trout had significantly less residue than raw. Smoking resulted in significantly greater losses of pesticides and total PCBs than other cooking methods but analyses of polynuclear aromatic hydrocarbons showed significant compound formation during smoking with higher levels occurring in high fat siscowets. Overall losses of pesticides and total PCBs ranged from a low of 21% for dieldrin to a high of 39% for chlordane complex. Most of the total losses were about 30% establishing that cooking is effective in reducing residues in these Great Lakes fish.

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in muscle and eggs of salmonid fishes from the Great Lakes

Abstract. Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were measured in dorsal muscle and eggs of coho salmon, lake trout, and chinook salmon collected from Lakes Superior, Michigan, and Huron (Michigan waters). Absolute and relative concentrations of PCDDs and PCDFs varied among sampling locations (inter- and intralake) and fish species. Fish collected from Bay City (Saginaw Bay) contained the greatest concentrations of PCDDs and PCDFs both in muscle and eggs. Among the three fish species, chinook salmon accumulated greater concentrations than did coho salmon or lake trout. Concentrations of PCDFs were greater than those of PCDDs in all fishes. OCDF and TCDF were the predominant congeners of PCDF, whereas OCDD and TCDD concentrations predominated in PCDDs. Homolog compositions of PCDDs and PCDFs suggested the existence of multiple local sources in various locations. Concentrations of PCDDs and PCDFs in eggs of fishes were significantly correlated with those in muscle.

Polychlorinated biphenyls: Photolysis of 3,4,3′,4′-tetrachlorobiphenyl and 4,4′-dichlorobiphenyl in solution

SummaryThe large difference in retention times for the photoproducts of 3,4,3′4′-tetrachlorobiphenyl can be explained on the basis of their chlorine content and the effect of vicinal chlorosubstitution as observed by V. Zitko and coworkers (4).The absence of biphenyl among the photoproducts of 4,4′-dichlorobiphenyl was not surprising since 4-chlorobiphenyl (λmax 203, 253) does not absorb at the wavelength of irradiation (λ>286), 4,4′-dichlorobiphenyl exhibits only marginal absorption at this wavelength (λmax 201, 259, 286) this explains the low yield of 4-chlorobiphenyl obtained (appx. .1%). The greater reactivity at the meta position may be the result of bond weakening due to steric interactions with the chlorine atom at the para position. Rate studies may provide an answer to this problem.

Evaluation of conventional and “organic” baby food brands for eight organochlorine and five botanical pesticides

Two lots of applesauce, pears, winter squash and carrots from each of two traditional commercials and one commercial “organic” brand of baby food were purchased from local retailers. These samples were analyzed for eight organochlorine (aldrin, dieldrin, cis-chlordane, p,p′-DDT, p,p′-DDE, p,p′-DDD, heptachlor, and hexachlorobenzene) and five botanical (nicotine, pyrethrin I, pyrethrin II, warfarin, and rotenone) pesticides in duplicate. The results indicated no detectable organochlorine pesticide residues at levels of detection between 4 and 11 pg/g, no detectable nicotine residues at the level of detection of 0.66 ng/g and no detectable pyrethrin I, pyrethrin II, warfarin and rotenone residues at levels of detection between 0.126 and 0.36 ng/g. Since no residues were found in any of the baby foods, there was no apparent distinction between the traditional commercial brands and the “organic” commercial brand of baby foods evaluated in this study.

Polychlorinated biphenyls, polybrominated biphenyls, and dioxin reduction during processing/cooking food.

This chapter presents information on the levels of environmental contaminants found in recent market basket surveys as well as the effect of processing and cooking on the reduction of these contaminants. Although consumers have expressed concern over the level of environmental contaminants in the food supply, market basket surveys involving over 8,000 analyses of foods ready-to-eat, found measurable amounts (ppb levels) of PCBs in only 24 foods. Processing/cooking has been shown to reduce PCBs by 20-100%. Although PBBs got into the food chain as the result of one incredible accident and thus are not expected to be found in foods today, cooking/processing was also effective in reducing PBBs. Dioxins are the result of combustion processes and chemical manufacturing processes. TCDD levels found in Great Lakes fish were in the low part per trillion level. Again, cooking and processing resulted in substantially less TCDD in fish as eaten.

Pesticides and total polychlorinated biphenyls residues in raw and cooked walleye and white bass harvested from the Great Lakes

To provide data for public health and other government officials to quantitate the degree of exposure a human might receive from consumption of commonly sought open water fish species prepared and cooked by commonly used methods, five species of Great Lakes fish were chosen. Data is presented for walleye harvested from Lakes Erie, Huron and Michigan which were baked and char-broiled as skin-on fillets with additional walleye from Lake Michigan being deep fat fried. Skin-on white bass fillets from Lakes Erie and Huron also were pan fried. Packed column PCB and pesticide analyses were conducted for all fish species by the Michigan Department of Public Health. The DDT complex (p,p{prime}DDT, p,p{prime}DDE and p,p{prime}DDD), dieldrin, hexa-chlorobenzene (HCB), chlorodane complex (alpha and gamma chlordane, oxychlordane, cis- and trans-nonachlor), toxaphene, heptachlor epoxide, and total PCBs (expressed as Arochlor{sup R} 1254) were found at above the minimum level of detection for many of the species studied. Residues were expressed as ppm wet tissue and then converted to micrograms per fillet to calculate the percentage loss due to cooking. 9 refs., 3 tabs.

Biologically Active Compounds in the Aquatic Environment: The Uptake and Distribution of [1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene], DDE by Chironomus tentans Fabricius (Diptera: Chironomidae)

Abstract The midge, Chironomus tentans, was exposed from egg through adult to varying concentrations (.07 to 2.2 ppb) of [1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene], DDE. The amount of DDE accumulated by the midge was determined by gas-liquid chromatography. The accumulation of DDE from aqueous solution and contaminated substrate by the midge as a function of DDE concentration and exposure time was determined, and the distribution of the accumulated DDE residue was quantitated (pupa, exuvia, adult, and egg mass). No attempt was made to differentiate between these two modes of uptake (water or substrate). The DDE accumulation by the midge demonstrated a dose-dependent relationship, accumulating DDE exponentially with increased concentration at a given exposure time. At any given concentration of DDE in the water, accumulation increased with increased exposure time. On a ppm basis the midges concentrated DDE approximately 20,000 times over that level which was present in the water. The exuvia did not de...

Bioactive compounds in the aquatic environment: Studies on the mode of uptake of DDE by the aquatic midge,Chironomus tentans (diptera: Chironomidae)

The mode of uptake of DDE-14C byChironomus tentans larvae was investigated. There was no difference in the amount of DDE-14C accumulated by live and dead fourth instar larvae as a function of exposure time. Dead and live larvae were also exposed to an aqueous and substrate source of DDE-14C contamination and again no differences were found in the amount of DDE-14C accumulated indicating passive accumulation. Cuticle surface area and DDE-14C uptake relationships were found to have a high degree of correlation. The amount of DDE-14C concentrated by the larvae was increased by manipulation of water hardness. Calcium and magnesium ion concentrations in the water were increased and a subsequent increase in DDE-14C accumulation by the larvae resulted. An adsorption-diffusion mechanism is proposed to account for the mode of uptake and biological concentration capabilities of the midge.

Bioactive compounds in the aquatic environment: Uptake and loss of DDT and dieldrin by freshwater mussels

Freshwater mussels were exposed to several concentrations of DDT [1, 1, 1-trichloro-2, 2-bis-(p-chlorophenyl) ethane] and HEOD (1, 2, 3, 4, 10, 10-hexachloro-6, 7-epoxy-1, 4, 4a, 5, 6, 7, 8a-octahydro-1, 4-endo-exo-5, 8-dimethanonaphthalene principal component of dieldrin) in natural lake water and in reconstituted distilled water, under continuous flow and constant temperature conditions. The mussels concentrate DDT approximately 2400 fold and HEOD 1200 fold in lake water; they concentrated DDT about 1000 fold in distilled water. The concentration of the insecticide chemicals in the mussels reaches equilibrium with the level in the water faster in lake water than in distilled water and the insecticide chemicals have a shorter half-life in the mussels than in lake water. The half-life of HEOD is 4.7 days in lake water compared to 13.6 days for total DDT residues in lake water. The insecticide chemical residue concentrations are highest in the digestive and reproductive tissue, and lowest in the muscle, mantle, and gill tissues. The residue concentrations are very low in the marsupia (abominal pouch), in the tests made in distilled water, but they are almost as great as those in the digestive-and reproductive tissue, in lake water.