William C. Sonzogni

Integrated environmental management: strengthening the conceptualization

Although espoused by many, integrated environmental management (IEM) has been difficult to accomplish in practice. There are many reasons for this shortfall, but certainly a key factor is the lack of agreement among scholars and practitioners regarding the concept and its defining elements. Our purpose here is to sharpen the conceptual basis for IEM by elaborating and pragmatically characterizing a framework for the practice of more integrated environmental management. We outline four fundamental dimensions of IEM: (1) comprehensive, (2) interconnective, (3) strategic, and (4) interactive/coordinative. IEM efforts in the Black EarthCreek watershed in Wisconsin illustrate specific attributes and examples pertaining to our conceptualization of IEM. Acceptance of the conceptual framework elaborated here should alleviate some of the confusion associated with IEM and help move this widely heralded approach from theory into practice.

Cyanobacteria (blue-green algae) in Wisconsin waters: acute and chronic toxicity.

Abstract Toxins produced by several species of cyanobacteria (blue-green algae) are a potentially serious environmental problem. These substances can be acutely toxic as evidenced by the death of livestock and other animals that have been exposed to them. In this study, samples collected from 102 sites in Wisconsin were analyzed for toxicity. Acute toxicity was tested by intraperitoneally injecting mice with lysed algal cells (identified to genus) and observing the effects. Chronic toxicity was tested using the Salmonella typhimurium mutagenicity test, the Bacillus subtilis multigene sporulation test and a chromosome breakage test using human lymphocytes. Mouse bioassay results showed that about 25% of the sites contained toxic algae, indicating acutely toxic algae are commonplace in Wisconsin waters. Bacterial assay results suggested the toxins were not directly mutagenic, but a chromosomal breakage test suggested the possibility that the algal toxins may be clastogenic. Overall, the results indicate that algal toxins may be more serious environmental hazards than generally recognized.

Weighted least-squares approach to calculating limits of detection and quantification by modeling variability as a function of concentration.

The limit of detection and limit of quantification are current critical issues in environmental testing. In most laboratories, limits are currently calculated on the basis of the standard deviation of replicate analyses at a single concentration. However, since the standard deviation depends on concentration, these single-concentration techniques result in limits that are directly dependent on spiking concentration. A more rigorous approach uses a weighted least-squares regression analysis of replicates spiked at a series of concentrations [Formula: see text] a calibration design. In this work, the use of weighted tolerance intervals is introduced for estimating detection and quantification limits. In addition, models for estimating the weights used in calculating weighted prediction intervals and weighted tolerance intervals are presented. Using this method, detection and quantification limits were calculated for gas chromatographic analyses of 16 polychlorinated biphenyls. Results show that the approach developed provides improved estimates of analytical limits and that the single-concentration approaches currently in wide use are seriously flawed. Future work should reduce the data needed for the calibration design approach so that more rigorous detection and quantification limits can be routinely applied.

Fish consumption and reproductive outcomes in Green Bay, Wisconsin.

Prenatal exposure to polychlorinated biphenyls (PCBs) and reproductive outcome was determined in a population of 1112 women during 1987-1989. The women studied were from the Green Bay, Wisconsin area, thereby providing a population with potential PCB exposure from Lake Michigan sport fish consumption. All women with positive pregnancy tests from two Green Bay prenatal clinics were asked to complete a self-administered questionnaire on fish consumption, health and reproductive history, and other relevant issues and to provide blood samples for PCB analysis. A positive correlation was found between the amount of Lake Michigan fish mothers claimed to consume and their PCB serum levels. After the pregnancy period, reproductive outcome measures (fetal wastage; stillbirths; and birth weight, birth length, head circumference, ponderal index, and birth weight percentiles for live births) were abstracted from hospital labor reports. Typical negative associations between birth size measures and consumption of caffeine, smoking, and alcohol were found. Birth size was positively associated with gestational age, birth order, weight gain during pregnancy, male babies, and rural residence. Birth size was also associated with PCB exposure; however contrary to expectations, a positive association was found (P < 0.044) for most mothers (the exception being those mothers who gained more than 34 lb during their pregnancy). PCB exposures were lower than the other studies that found that birth size was negatively associated with PCB exposure.

Correlations among human blood levels of specific PCB congeners and implications for epidemiologic studies

Specific congeners of PCBs may differ with respect to their human health risks. For epidemiologic studies, however, measuring levels of specific congeners--as compared with estimating the concentration of total PCBs present, may be of limited value if levels of specific congeners are highly correlated. We examined the correlations among levels of specific congeners in three groups: controls from a case-control study of breast cancer in North Carolina and two groups from Wisconsin with exposure to fish from contaminated waters. Levels of specific congeners were, in general, highly correlated (Pearson r > 0.80). However, the level of congener 180, a heptachlorobiphenyl, tended to be less correlated with levels of lower-chlorinated biphenyls. Among the implications of these findings are that measurement of a select group of congeners may yield essentially the same information as measurement of a large panel, and may be more cost efficient.

Polychlorinated biphenyl congeners in blood of Wisconsin sport fish consumers

As part of a study to evaluate the effect of chemical contaminants on Wisconsin sport fish consumers, measurements were made of polychlorinated biphenyl (PCB) congeners in human blood sera. A high resolution gas chromatography procedure was employed, with 13 individual congeners used as standards. Analytical recoveries and precision were >90% and replicates were always within ±30%. Total concentrations, obtained by summing quantified congeners, ranged from 0.6 to 27.1 μg/L. Conventional packed column PCB analysis, conducted on a subset of samples, gave higher total PCB results. On a congener specific basis, congeners 153 (245-245), 138 (234-245), 180 (2345-245) and 118 (245-34) were found most often. These congeners have been reported to be prominent in other matrices. Of the congeners found, 118, 138, and possibly 180 are potentially the most toxic (based on current toxicological information).

Analysis of polychlorobiphenyl congeners in Wisconsin fish

Because polychlorinated biphenyls (PCBs) in environmental or biological samples have for some time been identified and quantitated using Aroclor® mixtures to determine total PCBs, few data have been generated on individual congeners. Thus, methods were developed to allow the determination of individual congeners in various fish species of different sizes from Wisconsin waters. High resolution gas chromatography was used to separate the congeners. Established relative retention times were used for congener identification, while quantification was performed with five Aroclor® mixtures, with published values for congener weight percent composition, as standards. Among the most prominent congeners found in fish were congener numbers 153/132, 138, 66/95, 110, 180, 70/76, 146, 28/31, 149, 118, and 105. It is anticipated that information on the distribution of PCB congeners in the Great Lakes and other Wisconsin waters will be increasingly important from a toxicological standpoint, and, ultimately, for assessing the risk from PCBs to fish consumers.

Urinalysis of atrazine exposure in farm pesticide applicators.

This study compared three relatively common laboratory methods for the detection of atrazine (a triazine herbicide commonly used in US agriculture), and related metabolites in urine. Ninety-nine samples collected from atrazine applicators within 8 h post application were analyzed. Thirty-seven percent of applicators showed detectable levels (minimum=1.0 ng/ml) of deethylatrazine (an atrazine metabolite typically found in environmental samples) in their urine, based on gas chromatography-mass spectrometry (GC-MS) analysis (mean=14.2 ng/ml). Fifty applicator samples were tested using an enzyme-linked immunosorbent assay (ELISA) designed for the mercapturate metabolic product. Most of these samples (80%) had detectable levels of the mercapturate product. A triazine in water ELISAwas also used to test several diluted urine samples from atrazine applicators, and all samples were positive for triazines. Mediocre agreements between the three methods indicated that each detected distinct atrazine exposure products. The results indicate that single field applications of atrazine result in measurable pesticide doses to applicators and that the choice of field assay should depend on the exposure product to be evaluated.

New measurements of cyanobacterial toxins in natural waters using high performance liquid chromatography coupled to tandem mass spectrometry.

The presence and levels of the cyanobacterial toxins microcystin-LR, anatoxin-a, and cylindrospermopsin were measured in various Wisconsin waters where algal nuisance or bloom conditions were noted. Out of 74 samples analyzed, 36 had detectable levels of microcystin-LR (49%), and four had detectable levels of anatoxin-a (5%). Cylindrospermopsin, the toxin produced by Cylindrospermopsis (a warm water species that has been moving its range northward, including to Wisconsin), was not detected in the field samples tested. Concentrations of microcystin-LR ranged from 1.2 to 7600 microg L(-1). Anatoxin-a ranged from 0.68 to 1750 microg L(-1), which is the highest concentration reported from around the world. Cyanobacterial toxins, because of their high potency, deserve continued scrutiny by resource managers and public health officials responsible for recreational waters.

Metribuzin and metabolites in Wisconsin (U.S.A.) well water

Abstract Metribuzin is a commonly used pesticide in Wisconsin and elsewhere, although contamination of groundwater by metribuzin has received little attention. A technique using solid phase extraction and high performance liquid chromatography was optimized to allow measurement of metribuzin and its major metabolites—deaminated metribuzin (DA), diketometribuzin (DK) and deaminated diketometribuzin (DADK). Percent recoveries and precision of metribuzin and DA analyses were good. Recoveries and reproducibility of DADK were acceptable (about 65%). However, the recoveries for DK were low (about 35%; the precision of the analysis was good, however). Overall, accuracy and precision were as good as, or better than, reported in the literature. Metribuzin and metribuzin metabolites were found in most of the groundwater samples analyzed from a number of wells located in sandy soil areas of Wisconsin. The parent metribuzin compound was found at concentrations ranging from not detected to 10.2 μg/l, while metabolite concentrations ranged from not detected to nearly 2 μg/l. Metabolites, which have been rarely reported to occur in water, were found in most of the samples even when the parent compound was absent.