Ultraviolet and volatility loss of herbicides

Herbicide 2,4-D formulated as a urea-type polymer was readily destroyed by long-wave uv (356-nm) irradiation, whereas conventional 2,4-D was more resistant. The opposite relationship was noted for polymeric and conventional formulations of dicamba. Polymerized 2,4-D was more resistant to thermal degradation (60°C) than non-polymerized formulations. Ultraviolet degradation of polymerized 2,4-D was eliminated by the incorporation of RYLEX-H and UVINUL D-50, industrial uv absorbers. Exposure of polymeric dicamba to 60°C heat, followed by trapping of the volatile component, indicated that 21 percent was lost by thermal degradation and 46.6 percent by volatilization. Comparable values for non-polymerized dicamba were 37.9 and 60.1 percent.     

Absorption,metabolism and elimination of N,N-dimethylformamide in humans

Summary Excretion of N,N-dimethylformamide (DMF) and DMF metabolites N-hydroxymethyl-N-methylformamide (MF), N-hydroxymethyl-formamide (F) and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) has been monitored in the urine of volunteers during and after their 8-h exposure to DMF vapour at a concentration of 10, 30 and 60 mg · m^–3. The pulmonary ventilation in these experiments was typically about 101 · min^–1 and the retention in the respiratory tract was 90%. After exposure to 30 mg DMF · m^–3, the yield of compound determined in the urine represented 0.3% (DMF), 22.3% (MF), 13.2% (F) and 13.4% (AMCC) of the dose absorbed via the respiratory tract. The excretion curves of the particular compounds attained their maximum 6–8h (DMF), 6–8h (MF), 8–14h (F) and 24–34h (AMCC) after the start of the exposure. The half-times of excretion were approximately 2, 4, 7 and 23 h respectively. In contrast to slow elimination of AMCC after exposure to DMF, AMCC was eliminated rapidly after AMCC intake. This discrepancy could be explained by rate-limiting reversible protein binding of a reactive metabolic intermediate of DMF, possibly methylisocyanate.     

Hard hats vs. soft hearts: The conflict between principles and reality in child and adolescent care and treatment programs

Much of child care in volves quick reactions based on one's automatic pilot derived from how we were parented. This paper is about two seemingly universal automatic pilot systems—the hard hats and the soft hearts. Hard hats are behavior management and modification oriented, while soft hearts are psychodynamically and counselling oriented. Typically, the hard hats tend to have the upper hand due to the nature of our culture, and they therefore have the effect of preventing the contributions of the soft hearts from being realized. That all too frequently sets up a dominant culture and a resentful minority situation. To correct this imbalance, a value orientation from the top which emphasizes mutual respect and utilization is suggested.Grateful acknowledgement is made to Ray Peterson for his helpful suggestions in the preparation of this paper.     

Factor analysis of the psychosocial items of the EORTC QLQ-C30 in metastatic breast cancer patients participating in a psychosocial intervention study

The underlying factor structure of a subset of 12 items, which comprise the psychosocial subscales of the EORTC QLQ-C30 was explored in a group of women, all with metastatic breast cancer who were participating in a psychosocial intervention study. Two main factors were identified in this exploratory factor analysis, representing emotional distress and functional ability dimensions. A preliminary assessment of the external validity of the two factor structure was undertaken. The results support the validity of a summative emotional distress and functional ability score in this sample of patients. The functional ability score discriminated well for subgroups defined by clinical status indicators (e.g., performance status, pain, chemotherapy treatment, fatigue). The emotional distress subscale discriminated with respect to suffering, fatigue and sleep disturbance. Both subscales converged with related concepts measured by independent instruments, providing support for convergent validity. Summative index scores may be advantageous for application in particular research situations; applying quality adjustments in health policy analyses; for screening purposes; to monitor populations and make comparisons across broad groups and as stratification variables in clinical trials. Further research to confirm the 2 factor structure is required in other samples before the interpretation can be accepted with confidence.     

Lead,cadmium, and aluminum accumulation in the red swamp crayfishProcambarus clarkii G. collected from roadside drainage ditches in louisiana

The concentration of Pb, Cd, and Al in tissues of crayfishProcambarus clarkii were evaluated from several wetland sites located adjacent to roadways and were compared to crayfish harvested from a commercial site free from roadside influences. Abdominal muscle, hepatopancreas, alimentary tract, exoskeleton and blood were analyzed for metal content. Results indicated that levels of contamination obtained in almost all tissues of crayfish from roadside ditches contained significantly higher amounts of metals than those of the commercially harvested control crayfish (p = .05–.001). Detection limits of Pb, Cd, and Al ranged from 0.04 g Pb/g to 16.15 g Pb/g.001 g Cd/g to .13 g Cd/g, and 1.22 g Al/g to 981 g Al/g, respectively. Concentrations of Pb, Cd, and Al were highest in the hepatopancreas and alimentary tract. High levels of these elements were also detected in the exoskeleton. In contrast, muscle tissue was the least affected tissue. Several significant correlations among concentrations of metals were found when comparing a variety of tissues inProcambarus clarkii.     

“Mom” as a Protective Strategy Used by Children in Foster Care

How children use language impacts on their adjustment in foster care. It is important to understand the strategies children use with caregivers to protect themselves. The shortage of literature on how children cope in foster care is concerning because it limits placement workers in their ability to help children in care. This paper examines some of the reasons children take it upon themselves to call their foster caregiver Mom even when they have been discouraged from doing so. The phenomenon of children referring to foster caregivers as Mom is examined in this paper for how this strategy provides protection for children, theoretical explanations for how the use of Mom works, and for the opportunities its use brings.     

Biological aspects and self-evaluation of shiftwork adaptation

Summary Two male truck drivers working in a Brazilian cellulose plant and classifying themselves as well- and ill-adapted to a shiftwork schedule of 4 days-on and 1 day-off, participated in an autorhythmometric study. Psychophysiological self-ratings (calmness, stress and alertness), oral temperature measurements and urine collections (detection of K⁺,Na⁺ and 17-OH concentrations) were performed regularly during the waking period for 15 consecutive days during the shift schedule — the midday shift (11:00 to 19:00h), early-morning shift (03:00 to 11:00 h) and evening shift (18:00 to 02:00 h), including days-off. Cosine fitting of the data to a successive running one-day window revealed different individual temporal patterns, with the well-adapted subject showing a relatively stable phase relationship of the variables under study and the ill-adapted subject showing a less stable relationship. The different patterns could explain, at least partially, the fact that one subject feels adapted to shiftwork and the other not.Dedicated to the memory of Prof. Dr. Dr. Joseph Rutenfranz, former Director of the Institut für Arbeitsphysiologie, Dortmund, FRG, who contributed so much to the development of studies on occupational and environmental health     

Levels of β-HCH,HCB, p,p′-DDE,p,p′-DDT and PCBs in human milk from a continental town in Croatia,Yugoslavia

Summary Concentrations of -HCH, HCB, p,p-DDE, p,p-DDT and PCBs were determined by gas chromatography in 50 human milk samples collected from the general population during 1981/1982 in a continental town in Croatia (Yugoslavia). The samples were collected between one and 22 weeks after delivery from mothers breast-feeding one child only. The mothers' age was 18 to 31 years, and they were nursing their first or second child. All 50 samples contained -HCH, HCB, p,p-DDE and PCBs, whereas p,p-DDT was present in 37 samples. The concentrations of -HCH, HCB, p,p-DDE, p,p-DDT and PCBs expressed on a whole milk basis were (median in g/kg): 11, 7.1, 67, 7.3 and 22 respectively, and expressed on a fat basis (median in mg/kg): 0.28, 0.21, 1.9, 0.18 and 0.62 respectively. The fat content was 3.7% (median). PCBs were present in a mixture containing penta-, hexa- and heptachlorobiphenyls.     

Organochlorine accumulation by sentinel mallards at the Winston-Thomas sewage treatment plant, Bloomington, Indiana

Farm-raised 12-month-old female mallards (Anas platyrhynchos) were released at the Winston-Thomas sewage treatment plant, Bloomington, Indiana. Five mallards were sacrificed at the start of the study and at approximately 10-day intervals through day 100. Concentrations of polychlorinated biphenyls (PCBs) in carcasses increased linearly with time of exposure and exceeded 16 g/g wet weight by day 100; PCBs in breast muscle exceeded 3.9 g/g by day 100. These PCB values are among the highest recorded for wild or sentinel waterfowl. PCB concentrations in breast muscle (26–523 g/g lipid weight) were 50–1,000 times greater than human consumption guidelines for edible poultry in Canada (0.5 g/g lipid weight) and 9–176 times greater than consumption guidelines for edible poultry in the United States (3.0 g/g lipid weight). Additionally, PCB concentrations in carcass and breast muscle exceeded the threshold of the Great Lakes Sport Fish Consumption Advisory do not eat category (1.9 g/g wet weight) by day 20 and day 50, respectively. Hepatic cytochrome P450-associated monooxygenases including BROD (benzyloxyresorufin-O-dealkylase), EROD (ethoxyresorufin-O-dealkylase), and PROD (pentoxyresorufin-O-dealkylase) were induced over 5-fold compared to reference mallards. BROD, EROD, and PROD were each significantly correlated to total PCBs and to the toxicity of selected PCB congeners, relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin.     

Effect of environmental toxicants on enzyme biosynthesis: A comparison of β-galaclosidase, α-glucosidase and tryptophanase

Except for -galactosidase, little is known about the effect of environmental toxicants on enzyme induction. The information could be potentially useful for the development of low-cost and rapid ecotoxicity assays. The effect of toxicants on thede novo biosynthesis of three inducible enzymes, -galactosidase and tryptophanase inE. coli and -glucosidase inB. subtilis was investigated. Biosynthesis of -glucosidase was the most sensitive to environmental toxicants, particularly pentachlorophenol and sodium dodecyl sulfate. The sensitivity ofB. subtilis to toxicants was further increased when Tween^® 80 was incorporated in the growth medium.     

Urinary levels of 1-hydroxypyrene, 1-, 2-, 3-, and 4-hydroxyphenanthrene in females living in an industrial area of Germany

The concentrations of 1-hydroxypyrene (1-HOPYR), and 1-, 2-, 3-, and 4-hydroxyphenanthrene (HOPHE) as metabolites of pyrene and phenanthrene, were measured in urine samples collected from 124 housewives (27 smokers and 97 nonsmokers) living in Bottrop, an industrial city located in the Ruhr area in Germany. The urine samples were analyzed by a very sensitive and practical high-performance liquid chromatographic (HPLC) method using a two-column switching technique and a special precolumn packing material followed by fluorescence detection. The polycyclic aromatic hydrocarbon (PAH) metabolites are selectively enriched on the precolumn and separated from the matrix. Therefore, laborious clean-up steps were omitted. The above-mentioned PAH metabolites could be detected in all urine samples investigated. Smokers had significantly higher urine concentrations of 1-HOPYR (median 0.48 g/g creatinine), 3-HOPHE (median 0.61 g/g creatinine), 2-HOPHE (0.41 g/g creatinine) and 4-HOPHE (median 0.10 g/g creatinine) than non-smokers (median 0.15 g/g creatinine, 0.31 g/g creatinine, 0.31 g/g creatinine and 0.04g/g creatinine, respectively). The study shows that the influence of smoking is of such an order of magnitude that potential environmental exposure to PAH in this highly industrialized area is obscured by smoking habits. Furthermore, it can be concluded that the determination of 1-HOPYR, 1-, 2-, 3-, and 4-HOPHE in urine is a diagnostically useful method for the biological monitoring of persons environmentally exposed to PAH.     

Concentrations and chromatographic profile of DDT metabolites and polychlorobiphenyl (PCB) residues in stranded beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary,Canada

The concentrations and high resolution gas Chromatographic profiles of DDT metabolites and polychlorobiphenyl (PCB) congeners were determined in blubber, liver, kidney and lung tissue and milk samples of stranded beluga whales (Delphinapterus leucas) collected at localities along the coasts of the Saint Lawrence Estuary, Canada from November 1983 through December 1984. The analyses indicate that the major PCB components of the tissues were 2,2,5,5-tétra-, 2,2,4,4,5-penta-, 2,2,3,4,4,5-hexa-, 2,2,4,4,5,5-hexa-, 2, 2,3,3,4,5-hexa-, 2,3,3,5,5,6-hexa-, 2,2,3,4, 5,5,6-hepta- and 2,2,3,4,4,5,5-heptachlorobiphenyls. Although the highest organochlorine chemical concentrations were found primarily in the blubber, concentrations of 1.72 g/g for PCB and 2.04 g/g for DDT were determined in one milk sample. No correlation was established between PCB,p,p-DDE and DDT concentrations and the fat content of the kidney liver and lung tissues. The Chromatographie patterns of the PCB congeners were similar from one tissue to another with the exception of the kidney; the profile indicates the retention of PCB congeners which are minor components in the other tissues. Relations of residue concentrations between tissue are described and the significance of congener-specific PCB analysis is discussed in terms of the structureactivity effects on PCB persistence and toxicity.Portions of this work were presented at the Sixth Biennial Conference on the Biology of Marine Mammals, Vancouver, British Columbia, November 22–26, 1985.     

The evaluation of pornography: Effects of attitude and perceived physiological reaction

Twenty-three medical and 28 nonmedical male student Ss read four erotic prose passages and then rated each on obscenity, censorship, and four semantic differential evaluation scales. Ss were given varying levels of false (experimenter-controlled) GSR feedback for each stimulus passage, as well as different explanations of the significance of this arousal feedback. Four-way analyses of variance showed that low Stolerance of erotica, pedophelic passage content, and GSR feedback indicating physiological arousal resulted in passages being labeled as more obscene and unfavorable. Explanations to Ss that GSR feed-back indicated sexual arousal resulted in more favorable ratings by the medical Ss and interacted with passage type for the nonmedical Ss. Concurrently monitored heart rate was not significantly influenced by any of the experimental variables and was (with one marginal exception) uncorrelated with any of the dependent labeling variables. An earlier version of this article was presented at the XVIIth International Congress of Applied Psychology, Liege, Belgium, July 1971.     

Blood toluene as a biological index of environmental toluene exposure in the “normal” population and in occupationally exposed workers immediately after exposure and 16 hours later

Blood toluene was measured in a group of 100 workers occupationally exposed to a mean 8-h environmental toluene concentration of 128 g/l (34 ppm), and in a group of 269 normal subjects without occupational exposure to toluene. The mean blood toluene of the workers at the end of the shift and the following morning, after 16 h, was 457 and 38 g/l, respectively. The normal subjects had a blood toluene level of 1.1 g/l. On the basis of the highly significant correlation between blood toluene and occupational exposure, it can be calculated that environmental toluene exposure of 188 and 377 g/l (50 and 100 ppm) gives end-of-shift blood toluene levels of 690 and 1390 g/l, respectively. The corresponding blood toluene levels on the following morning are 50 and 100 /l, respectively.     

Measurement of manganese amelioration of cadmium toxicity inChlorella pyrenoidosa using turbidostat culture

Cadmium (Cd) toxicity and amelioration of Cd toxicity by Mn were measured inChlorella pyrenoidosa, using turbidostat culture. The responses were measured in terms of the maximum specific growth rate, _max, of the populations. In turbidostat culture _max is a dependent variable that can be measured continuously. Cd (as CdCl₂· 2.5 H₂O) was added to control populations at a concentration of 1.8 M Cd. Toxicity was expressed after a 5 generation lag and resulted in a _max steady state 62% lower than the initial control after 2 generations. With continued Cd exposure, Mn (as MnCl₂ · 6H₂O) was then added stepwise to a concentration of 10.4 M Mn which caused a rapid, immediate increase in _max followed by linear increase until a steady-state plateau was reached at a _max 90% of control. The ameliorative response spanned 20 culture generations. After addition of Mn (10.4 M), cellular Cd concentration did not change and cellular Mn concentration increased. Increase in mean cell size accompanied Cd exposure and was significantly decreased when supplemented with 10.4 M Mn. Possible mechanisms of the amelioration are discussed.     

Cytogenetic studies of herbicide interactions in vitro and in vivo using atrazine and linuron

The herbicides atrazine and linuron, found in Wisconsin's groundwater, were tested alone and in combination, both in vivo and in vitro, to determine their individual and combined genotoxic effects. Human lymphocytes exposed in vitro to either 1 g/ml linuron or 0.001 g/ml atrazine showed little chromosome damage, whereas significant chromosome damage was observed in lymphocytes simultaneously exposed to 0.5 g/ml linuron and 0.0005 g/ml atrazine, suggesting at least an additive model. In another experiment, mice were fed 20 g/ml atrazine, 10 g/ml linuron, or a combination of 10 g/ml atrazine and 5 g/ml linuron in their drinking water for 90 days, after which bone marrow cells and cultured splenocytes were examined for chromosomal damage. None of the treatment groups showed chromosome damage in bone marrow, whereas the cultured splenocytes demonstrated damage in all treatment groups. These experiments suggest that, prior to assessing the risk of a herbicide, it may be necessary to test it in combinations which mimic the mixtures which would occur under field conditions, such as in contaminated groundwater.     

Toxicity of mercury,copper, nickel,lead, and cobalt to embryos and larvae of zebrafish,Brachydanio rerio

The toxicity of mercury (HgCl₂), copper (CuCl₂: 5 H₂O), nickel (NiSO₄: 6 H₂O), lead (Pb(CH₃COO)₂: 3 H₂O) and cobalt (CoCl₂: 6 H₂O) was studied under standardized conditions in embryos and larvae of the zebrafish,Brachydanio rerio. Exposures were started at the blastula stage (2–4 h after spawning) and the effects on hatching and survival were monitored daily for 16 days. Copper and nickel were more specific inhibitors of hatching than cobalt, lead, and mercury. Nominal no effect concentrations determined from the dose-response relationships (ZEPs, Zero Equivalent Points) for effect on hatching time were 0.05 g Cu/L, 10 g Hg/L, 20 g Pb/L, 40 g Ni/L and 3,840 g Co/L, and those for effect on survival time were 0.25 g Cu/L, 1.2 g Hg/L, 30 g Pb/L, 80 g Ni/L, and 60 g Co/L. The no effect concentrations for Ni, Hg and Pb are consistent with previously reported MATC values for sensitive species of fish. The no effect concentrations for copper are 1–2 orders of magnitude lower than previously reported values. The major reason for the latter discrepancy was considered to be the absence of organics that can complex copper ions in the reconstituted water that we used, which had a hardness of 100 mg/L (as CaCO₃) and a pH of 7.5–7.7. Unexposed controls were started with embryos from different parental zebrafishes and the parental-caused variability in early embryo mortality, median hatching time and median survival time were estimated.     

Percutaneous absorption of N,N-dimethylformamide in humans

Summary Skin penetration fo N,N-dimethylformamide (DMF) liquid or vapour was studied in volunteers. Exposure to liquid DMF was performed in two ways: in a dipping experiment, one hand was dipped up to the wrist in DMF for 2–20 min, while in a patch experiment, 2 mmol DMF was applied to the skin and allowed to be absorbed completely. The period of exposure to DMF vapour (50 mg · m^–3) was 4 h. The DMF metabolites N-hydroxymethyl-N-methylformamide (MF), N-hydroxymethylformamide (F), and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) were monitored in the urine. Liquid DMF was absorbed through the skin at a rate of 9.4 mg · cm^–2 · h^–1. Percutaneous absorption of DMF vapour depended strongly on ambient temperature and humidity and accounted for 13%–36% of totally excreted MF. The results suggest that skin absorption of liquid DMF is likely to contribute to occupational exposure substantially more than penetration of DMF vapour. The yield of metabolites after transdermal DMF absorption was only half of that seen after pulmonary absorption. Elimination of MF and F but not that of AMCC was delayed, which supports the contention that AMCC should be used instead of MF as the most suitable biomarker of DMF in cases where percutaneous intake can occur.     

Effects of nabam on developingXenopus laevis embryos: Minimum concentration,biological stability,and degradative products

This study was carried out to determine 1) the minimum concentration at which the fungicide ethylenebisdithiocarbamate disodium salt (nabam) would induce malformations in developingXenopus laevis embryos, 2) whether nabam in solution retained toxicological and teratogenic effects over long periods of time, 3) to compare the toxic and teratogenic effects of nabam's degradative products ethylene thiourea and ethylene diamine, 4) to compare toxic and teratogenic effects of the related substances methyl isothiocyanate and sodium thiocyanate, and 5) to compare the effects of combinations of these substances.Xenopus laevis embryos at yolk plug stage (Nieukoop and Faber stages 10–12) were exposed to various concentrations of fresh and one- to seven-week old nabam solutions, ethylene thiourea, ethylene diamine, methyl isothiocyanate, sodium thiocyanate, and combinations of some of these substances. Fresh nabam solutions induced malformations of the notochord in a majority of embryos at concentrations as low as 40 g/L. Embryos treated with 40 g/L nabam stored 1–7 weeks developed normally. Embryos treated with 100 g/L nabam stored 1–7 weeks developed severe malformations of the notochord, delayed pigmentation of the eye, and increased mortality. In addition, embryos exposed to 100 g/L nabam stored 4–7 weeks also experienced delayed development of the gut and a general decrease in size. Embryos exposed to fresh 100 g/L nabam solutions developed only malformations of the notochord. Concentrations of methyl isothiocyanate of less than 1.0 g/L were sublethal. Methyl isothiocyanate (1.0–1,000 g/L) was extremely toxic with 100% mortality recorded by day 7 in all groups. Sodium thiocyanate, ethylene thiourea, and ethylene diamine (100–10,000 g/L) were neither toxic nor teratogenic. Combinations of ethylene thiourea and methyl isothiocyanate at or beyond 5,000 g/L, or 1.0 g/L respectively were acutely lethal. At concentrations of 100–1,000 /L ethylene thiourea and 0.01–0.1 g/L methyl isothiocyanate, the tadpoles that hatched had swollen and kinked notochords, similar to animals exposed to fresh 40 g/L nabam. Thus, the aquatic environment when contaminated with very low levels of the fungicide nabam is hazardous to the development of amphibian embryos.     

Contaminant residues in fish and sediments from lakes in the Atchafalaya River Basin (Louisiana)

Conversion of bottomland hardwood forests agricultural land has reduced habitat and water quality in many lakes in the floodplain of the lower Mississippi River. The objectives of this study were to ascertain current contaminant residue concentrations in fish and sediment from lakes in the Atchafalaya River Basin and to determine the influence of overflow and agricultural land use on contaminant levels. Fish and sediment samples were collected from eight lakes that differed in overflow (no overflow, headwater overflow, backwater overflow) and land-use characteristics (presence or absence of agricultural land). Residue analysis of 24 sediment and 82 fish samples collected from the study lakes showed that contaminant residues were uniformly low. Total DDT concentrations, consisting mainly of DDE, were found in 98% of the fish samples and generally were the highest residues though they rarely exceeded 0.50 g/g. Dieldrin, -BHC and -BHC, in concentrations rarely exceeding 0.05 g/g, were detected in about 50% of the fish samples. Total organochlorine pesticide and PCB residues were less than 2.00 g/g in all fish from all lakes, except for a 3.46 g/g total in spotted gar (Lepisosteus oculatus) from one lake. Sediments were free from pesticide residues except for occasional traces (0.01 g/g) of -BHC. Metal residue concentrations in fish and sediment samples were typical of uncontaminated areas. Lake systems in the Atchafalaya River Basin appeared to be relatively uncontaminated by agricultural pesticides, but metal and organic residues in fish were similar from lakes with the same land-use and overflow characteristics.