Evaluation of a tape-stripping technique for measuring dermal exposure to pyrene and benzo(a)pyrene

Epidemiological studies have shown an increased incidence of cancer among workers occupationally exposed to polycyclic aromatic hydrocarbons (PAHs). As the dermal route is considered important for exposure to PAHs in the workplace, the aim of this study was to develop and evaluate a tape-stripping technique for monitoring dermal exposure to pyrene and benzo(a)pyrene. The tape-stripping method was evaluated by applying different concentrations of pyrene and benzo(a)pyrene directly onto tape strips (spiked tapes), clean glass plates, and on the skin of five volunteers. The glass plates were stripped using a single strip of tape and the skin of the volunteers was stripped with five consecutive strips of tape after 0 and 30 minutes. The method was also tested on five chimney sweeps at three exposure sites. High-performance liquid chromatography with fluorescence detection was employed for the quantification of pyrene and benzo(a)pyrene. The mean recovery from the spiked tapes was 97% for pyrene and 93% for benzo(a)pyrene. The mean overall recovery from the glass plates was 88% and 76% for pyrene and 88 and 85% for benzo(a)pyrene. The recovery from human skin was 70% and 63% for pyrene and 60 and 54% for benzo(a)pyrene, after 0 and 30 minutes, respectively. A concentration gradient was clearly detected between the five consecutive strips. Detectable amounts of pyrene and benzo(a)pyrene were found on all chimney sweeps at all exposure sites. This method can thus be used to detect and quantify dermal exposure to pyrene and benzo(a)pyrene. The results also show that pyrene and benzo(a)pyrene may be taken up by the skin.     

Educating the South Pacific about the environment

Summary Environmental education is currently fashionable. However, some educators are viewing it with suspicion as a trendy subject which will disrupt their carefully planned syllabii which are geared largely towards the passing of examinations. In the South Pacific there have been a number of attempts to increase people's awareness of their surroundings and to build up a respect for what is loosely termed our physical environment. These programmes have included, increasing the amount of environmental examples in a range of primary and secondary school subjects, formal courses in environmental planning at the tertiary level, and conservation messages through the media.Dr Jenny Bryant is a Lecturer in Geography at the University of the South Pacific, and recently Secretary, now Acting Chairperson, of the South Pacific Action Committee for Human Ecology and the Environment (SPACHEE).     

Low concentrations of atrazine, glyphosate, 2,4-dichlorophenoxyacetic acid, and triadimefon exposures have diverse effects on Xenopus laevis organ morphogenesis

Many chemicals are released into the environment, and chemical contamination has been suggested as a contributing factor to amphibian declines. To add to a growing body of knowledge about the impact of individual chemicals on non-target organisms, we examined the specificity of deformities induced by exposure to four pesticides (atrazine, 2,4-dichloropheoxyacetic acid (2,4-D), triadimefon, and glyphosate) in the model amphibian species, Xenopus laevis. We focused on the period of organ morphogenesis, as it is frequently found to be particularly sensitive to chemical exposure yet also commonly overlooked.We found similar levels of intestine malformations and edemas, as well as disruption of skeletal muscle, in atrazine and triadimefon exposed tadpoles. The e ects of 2,4-D were only apparent at the highest concentrations we examined; glyphosate did not induce dramatic malformations at the concentrations tested. While researchers have shown that it is important to understand how chemical mixtures a ect non-target organisms, our results suggest that it is first crucial to determine how these chemicals act independently in order to be able to identify consequences of individual pesticide exposure.     

Seasonal and Flood‐Induced Variations in Groundwater–Surface Water Exchange in a Northern Coldwater Fishery

Groundwater upwelling is important to coldwater fisheries survival. This study used stable isotopes to identify upwelling zones within a watershed, then combined isotope analyses with reach‐scale monitoring to measure surface water–groundwater exchange over time. Research focused on Amity Creek, Minnesota, a basin that exemplifies conditions limiting coldwater species survival along Lake Superior's North Shore where shallow bedrock limits groundwater capacity, lowering baseflows and increasing temperatures. Groundwater‐fed reaches were identified through synoptic isotope sampling, with results highlighting the importance of isolated shallow surficial aquifers (glacially derived sands and gravels) for providing cold baseflow waters. In an alluvial reach, monitoring well results show groundwater was stored in two reservoirs: one that reacts quickly to changes in stream levels, and one that remained isotopically isolated under most flow conditions, but which helps sustain summer baseflows for weeks to months. A 500‐year flood demonstrated the capacity of high‐flow events to alter surface water–groundwater connectivity. The previously isolated reservoir was exchanged or mixed during the flood pulse, while incision lowered the water table for years. The results here provide insight for streams that lack substantial groundwater inputs yet maintain coldwater species at risk in a warming climate and an approach for managers seeking to protect cold baseflow sources.     

Socio-economic differentiation in the trade of wildlife species for traditional medicines in the Lowveld,South Africa: Implications for resource management initiatives

Surveys of trade in wildlife products utilised in traditional medicine were conducted between 1997 and 1999 on the western boundary of the Kruger National Park, South Africa. Although the extent of trade and numbers of people operating in this sector were lower than other regions of South Africa, this study again highlighted the value of indigenous wildlife products to subsistence economies. Apart from cultural diversity, socioeconomic differentiation occurred at a number of levels. (i) There were socio-economic differences between the traders and vendors. (ii) Gender differences were apparent, with women earning significantly less than men and having to undergo more social challenges in their operation in the market place. (iii) Operational differences were noted between the vendors and traders, as well as between the street and pension day vendors. (iv) Multidimensional Scaling (MDS) highlighted the socio-economic differentiation at the household level, emphasizing in particular one of the most vulnerable groups, the elderly. The potential influence of this socio-economic differentiation needs to be considered during the development of Community-Based Conservation programmes, if the dual aims of conserving biodiversity and improving the lives and livelihoods of those who traditionally rely on medicinal plants are to be met.     

Temporal and spatial trends of PCBs,DDTs, HCHs,and HCB in Swedish marine biota 1969–2012

In the 1960s, the Baltic Sea was severely polluted by organic contaminants such as PCBs, HCHs, HCB, and DDTs. Elevated concentrations caused severe adverse effects in Baltic biota. Since then, these substances have been monitored temporally and spatially in Baltic biota, primarily in herring (Clupea harengus) and in guillemot (Uria aalge) egg, but also in cod (Gadus morhua), perch (Perca fluviatilis), eelpout (Zoarces viviparous), and blue mussel (Mytilus edulis). These chemicals were banned in Sweden in the late 1970s/early 1980s. Since the start of monitoring, overall significant decreases of about 70–90 % have been observed. However, concentrations are still higher in the Baltic Sea than in, for example, the North Sea. CB-118 and DDE exceed the suggested target concentrations (24 µg kg^?1 lipid weight and 5 µg kg^?1 wet weight, respectively) at certain sites in some of the monitored species, showing that concentrations may still be too high to protect the most sensitive organisms.     

Screening maternal serum alpha-fetoprotein levels and human parvovirus antibodies

The association between gestational infection with human parvovirus (B19) and fetal loss has increased interest in this virus and demand for diagnostic testing. However, serological assays for B19 are not yet widely available. Maternal serum alpha-fetoprotein (MSAFP) testing is commonly used during the second trimester to screen for various fetal defects. We attempted to determine whether an elevated level of MSAFP would be an appropriate indication for B19-specific tests. Over a 26-month period, MSAFP tests were performed at Michigan State University for 21 392 women. Sera remaining after that testing were stored frozen. Of these, 22 case samples—from women with MSAFP levels greater than 3·0 multiples of the median (MOM) and pregnancies that ended in fetal loss—and 44 matched control samples—from women with MSAFP levels greater than 0·4 and less than 2·2 MOM and live births at term—were tested for B19 antibodies. None of the 66 samples was IgM positive, while 33 (50 per cent) were IgG positive. The presence of IgG was not significantly associated with case or control status (matched odds ratio=0·77, 95 per cent confidence interval 0·28–2·11). These findings are consistent with other studies indicating prior infection in approximately half of adults and suggest that elevated screening MSAFP levels, in the absence of other evidence of B19 infection, should not prompt B19-specific testing.     

Boating and navigation activities influence the recruitment of fish in a Baltic Sea archipelago area

We studied the effects of boating and navigation activities on the recruitment of coastal fish in the Stockholm archipelago in the NW Baltic proper. The impacts were quantified by sampling metamorphosed young-of-the-year (Y-O-Y) fish in inlets adjacent to i) routes for medium-sized passenger ferries; ii) berths (small marinas) with small boats; and iii) references. Species with high preference for vegetation were negatively influenced by boating and navigation activities and species with low preference positively influenced. Pike (Esox lucius) Y-O-Y were significantly more abundant in reference areas, while bleak (Alburnus alburnus) were more abundant in dredged marinas. No statistically significant patterns were identified for perch (Perca fluviatilis) although there was a trend of low abundance along ferry routes. Many species of nearshore fishes are dependent on submerged vegetation as spawning and larval substrate, structural refuge and feeding habitat. Our results suggest that the negative effects from boating and navigation activities on the coverage and height of vegetation, especially on species of Chara and Potamogeton spp., may contribute to changes in the Y-O-Y fish community.