Improving the accuracy of sediment-associated constituent concentrations in whole storm water samples by wet-sieving

Sand-sized particles (>63 microm) in whole storm water samples collected from urban runoff have the potential to produce data with substantial bias and/or poor precision both during sample splitting and laboratory analysis. New techniques were evaluated in an effort to overcome some of the limitations associated with sample splitting and analyzing whole storm water samples containing sand-sized particles. Wet-sieving separates sand-sized particles from a whole storm water sample. Once separated, both the sieved solids and the remaining aqueous (water suspension of particles less than 63 microm) samples were analyzed for total recoverable metals using a modification of USEPA Method 200.7. The modified version digests the entire sample, rather than an aliquot, of the sample. Using a total recoverable acid digestion on the entire contents of the sieved solid and aqueous samples improved the accuracy of the derived sediment-associated constituent concentrations. Concentration values of sieved solid and aqueous samples can later be summed to determine an event mean concentration.     

Acute exposure to chemicals during ‘do-it-yourself’ activities: survey of enquiries to the Swedish Poisons Information Centre in 1996

In 1996 the Swedish Poisons Information Centre performed a follow-up study concerning poisonings related to ‘do-it-yourself’ activities. The study was supported by the National Institute of Public Health in Sweden. The objectives were to investigate and define monthly variations, route of exposure, type of products and, in particular, exposures to corrosives, age and sex groups, place of treatment, severity of symptoms, place of the accident, special risk products and risk situations. The Poisons Information Centre was contacted concerning 1609 cases, with a peak during the summer months. There was no or uncertain connection between exposure and symptoms in 117 cases. This means that 1492 cases were left to study. Inhalation and eye exposure were the predominant routes, followed by skin exposure and ingestion. Cleaning agents were the most common type of products involved. Of the 1492 cases included in the study 1033 were possible to follow up. Among these, 20–29 year olds and 30–39 year olds predominated, and there was a dominance for men. In total, 28% of those exposed were subject to medical attention, either in hospital or in outpatient clinics. According to the Poisoning Severity Score 78% had mild (grade 1) and 7% moderate (grade 2) symptoms. There were no severe intoxications and no deaths. Severity grade 2 occurred 3.6 times more often among those with exposures involving risk of corrosive damage than among others in the study population. Most accidents occurred in the home. Special risk products and risk situations were exposure to corrosive products, release of chlorine when mixing hypochlorite and acid, ‘fire-eating’, siphoning gasoline and diesel fuel, welding, and inhalation of carbon monoxide from exhaust gases. The Swedish Poisons Information Centre registered 1609 cases of poisoning accidents during ‘do-it-yourself’ activities, which means an average of four to five cases per day. Although this type of accidents is not uncommon, significant poisoning seems to be rare. Some special risk situations were identified.     

A procedure to estimate worst-case air quality in complex terrain

Using a straightforward synoptic climatological analysis scheme, it is shown that the potential for an area to experience air quality degradation due to local sources is highest under polar subtropical highs. With respect to polar highs, the problem is most severe when the sun angle is low and snow covers the ground, and the polar high persists for a long period of time. A simple algorithm is introduced which is designed to estimate worst-case impact in a trapping valley. The potential for the accumulation of air pollution in such valleys due to the persistence of a polar high in a region, is ignored in current regulatory air quality assessments. Trapping valleys and synoptic flow stagnation often occur in wilderness areas. Refined air quality assessments are shown to be possible using a mesoscale meteorological model and a pollution dispersion model. These tools permit quantitative assessments of pollution build-up from local sources as a result of the recirculation of the local air. This tool, along with the synoptic climatological classification scheme, also permits an evaluation of the fractional contribution of long range versus local sources in the air quality degradation in a region. Areas near the center of a polar or subtropical surface high pressure system, for instance, appear to be dominated by local sources, if they exist, whereas in the vicinity of extratropical cyclones, long-range transport is usually much more important.     

Emergency room evidence on the role of alcohol intoxication in injury at work in the U.S.

Alcohol is a known risk factor for many kinds of injuries, but past research has failed to implicate alcohol intoxication as a major cause of work injuries in the U.S. Local and regional studies have indicated that alcohol-related injuries are relatively less common in work settings than non-work settings. In a six-month study, the National Electronic Injury Surveillance System collected the first national sample data on alcohol and injuries presenting to hospital emergency rooms. The study included both work injuries and product-related non-work injuries. Alcohol intoxication was ascertained by emergency room chart review. Alcohol involvement was much lower than in other studies, probably because of poor sensitivity in ascertainment, and it was 10 times lower among work injuries than non-work injuries. “Non-work activities at the time of injury” were a significant risk factor for alcohol-related injuries (odds ratio = 7). Thus, results of this national study are consistent with previous research in finding that alcohol poses a greater risk for nonwork injury than for work injury.     

Embryonic and parental preferences for incubation temperature in herring gulls: implications for parent-offspring conflict

According to Trivers (1974), parent-offspring (P-O) conflict arises because offspring are selected to solicit more care than parents are selected to provide. However, should benefits fail to increase with increasing care, the offspring optimum can be reduced to the point where predicted P-O conflict vanishes. We examined offspring demand and parental care in such a benefit-limited system in herring gulls (Larus argentatus). In this species, parents typically neglect their lasthatched (C-) egg during the final hours of hatching (pipped-egg stage), allowing mean temperature to drop by about 4°C, to near 33°C. Other studies indicate that no increased offspring benefit arises from increasing pipped egg incubation temperature above that level, but embryo damage occurs if temperature drops lower. In such a system, P-O conflict over preferred incubation temperature is predicted to be minimal or absent. We assessed phenotypic manifestations of conflict by determining incubation temperature preferences of parent and offspring independently. Temperature provided solely by parental initiative was 33.9°C (artificial eggs, corrected for embryonic heat production). Preferred incubation temperature of pipped embryos was measured by exposing them to moderate chilling (20°C) punctuated by 4-min periods of rewarming when they called. Temperature of vocally thermoregulating embryos stabilized around a mean of 32.9–33.4°C, about 0.5–1.0°C below parental preference. Acting independently, parents and embryos each maintained egg temperature at or near minimum developmentally safe levels. Results provided no evidence for phenotypic conflict, as predicted by a benefit-limited version of Trivers' P-O conflict model. Benefit limitation may also be relevant to P-O conflict in other contexts such as feeding of newly-hatched young.     

Empirical and theoretical evidence concerning the response of the earth's ice and snow cover to a global temperature increase

As a guide to the possible effects of a CO₂-induced warming on the cryosphere, we review the effects of three warm periods in the past, and out theoretical understanding of fluctuations in mountain glaciers, the Greenland and Antarctic ice sheets, ground ice, sea ice and seasonal snow cover. Between 1890 and 1940 A.D. the glaciated area in Switzerland was reduced by over 25%. In the Hypsithermal, at about 6000 BP, ground ice in Eurasia retreated northward by several hundred kilometres. In the interglacial Stage 5e, at about 120 000 BP, global sea-level rose by over 6 m. Fluctuations of mountain glaciers depend on mesoscale “weather” and on their mechanical response to it. Any melting of the Greenland ice sheet is likely to be slow in human terms. The West Antarctic ice sheet (its base below sea-level) is susceptible to an ungrounding, and such an event may have been the cause of the sea-level rise above. The East Antarctic ice sheet is susceptible to mechanical “surges”, which might be triggered by a warming at its margin. Both an ungrounding and a surge might occupy less than 100 yr, and are potetially the most important ice changes in human terms. Modelling studies suggest that a 5°C warming would remove the Arctic pack ice in summer, and this may be the most significant effect for further climatic change.     

From eco-management and audit (EMAS) to sustainability management and audit (SMAS)

The local authority version of the Eco-Management and Audit Scheme (LA-EMAS) can already be used as a tool for managing towards sustainability. But it can also be used in a much less ambitious 'procedural' way. This article suggests how LA-EMAS could be developed more fully into a sustainability management tool embracing social issues, a concern over environmental carrying capacities, and stakeholder involvement. This raises questions which should be considered in the run-up to the review of the EMAS regulation in 1998.     

Ambient concentrations and correlations of hydrocarbons and halocarbons in the vicinity of an airport

Concentrations of sixteen volatile hydrocarbons present in internal combustion engine exhaust gases and two halogenated hydrocarbons have been measured in ambient air samples at six sites around Gatwick Airport. Correlations between their concentrations have been drawn in an attempt to establish the exact nature of the sources of these emissions, together with consideration of the overall hydrocarbon profiles.