Land application of wastewater and state water law :

Mode of access: Internet.

Removing potential organic carcinogens and precursors from drinking water /

Mode of access: Internet.

History, stories and legends of South Carolina,

Mode of access: Internet.

Occurrence and elimination of cyanobacterial toxins in two Australian drinking water treatment plants

In Australian freshwaters, Anabaena circinalis, Microcystis spp. and Cylindrospermopsis raciborskii are the dominant toxic cyanobacteria. Many of these Surface waters are used as drinking water resources. Therefore, the National Health and Medical Research Council of Australia set a guideline for MC-LR toxicity equivalents of 1.3 mug/l drinking, water. However, due to lack of adequate data, no guideline values for paralytic shellfish poisons (PSPs) (e.g. saxitoxins) or cylindrospermopsin (CYN) have been set. In this spot check. the concentration of microcystins (MCs), PSPs and CYN were determined by ADDA-ELISA, cPPA, HPLC-DAD and/or HPLC-MS/MS, respectively, in two water treatment plants in Queensland/Australia and compared to phytoplankton data collected by Queensland Health, Brisbane. Depending on the predominant cyanobacterial species in a bloom, concentrations of up to 8.0, 17.0 and 1.3 mug/l were found for MCs, PSPs and CYN, respectively. However, only traces (< 1.0 mug/l) of these toxins were detected in final water (final product of the drinking water treatment plant) and tap water (household sample). Despite the low concentrations of toxins detected in drinking water, a further reduction of cyanobacterial toxins is recommended to guarantee public safety. (C) 2004 Elsevier Ltd. All rights reserved.

Year-round presence of dugongs in Pumicestone Passage, south-east Queensland, examined in relation to water temperature and seagrass distribution

Pumicestone Passage is a narrow waterway that lies to the north of and adjacent to Moreton Bay, and between mainland Queensland and Bribie Island, Australia. Anecdotal reports have suggested that the Passage is home to dugongs year-round despite winter water temperatures that are known to cause dugongs to migrate elsewhere. To examine the pattern of distribution and abundance of dugongs within the passage on a year-round basis, eight years of sightings data collected by a charter boat operator were examined. Dedicated aerial surveys of the passage were also conducted at two-monthly intervals over two years, and more intensively over a single winter. Dugong sightings were examined in relation to water temperatures and seagrass prevalence. The number of dugongs sighted in the area on any one survey varied from 0 to 13. Dugongs were seen in all months of the year and in each of the eight winters, indicating that Pumicestone Passage is used year-round despite winter water temperatures dropping to below 18 degrees C from June to August inclusive and below 16 degrees C in June. All dugong sightings occurred in the southern part of the passage, south of Tripcony Bight. Dugongs were associated with shallows that support Halophila and Halodule species of seagrass, food species that are favoured elsewhere in their range. The northern part of the passage also supports seagrasses that are eaten by dugongs and has water temperature ranges that are not appreciably different to those of the southern passage. However, the narrow channels and very shallow nature of the northern passage provides little to no deep-water refugia for dugongs and the seagrass beds are less extensive. This study suggests that southern Pumicestone Passage requires protection concomitant with it being a year-round refuge of the vulnerable dugong.

Preliminary investigations into oxidation of paralytic shellfish poisons (saxitoxins and derivatives) in drinking water by chlorine

The fresh water cyanobacterium Anabaena circinalis produces saxitoxin (STX) and several other toxins with similar basic structural skeleton. Collectively, these toxins are known as Paralytic Shellfish Poisons or PSPs. These toxins are water soluble and can escape into the water body after cell lysis. The presence of these toxins in drinking water is a serious threat to human health. The present work has shown that Paralytic Shellfish Poisons (PSPs) in drinking water can be removed by chlorination at high pH (>9.0), provided a residual of 0.5 mg/L of free chlorine is present after 30 minutes of contact time.

The influence of aluminium, administered in the diet and in drinking water, on biopterin metabolism

To investigate the neurotoxic effects of aluminium (Al) three studies were carried out in which Al was administered: 1) in the diet, 2) as a suspension of aluminium acetate in drinking water and 3) a long-term study in which aluminosilicates were incorporated into a pelleted diet. Admistration of Al in the drinking water significantly reduced total brain biopterin. However, no significant affect of Al in the diet on total bipterins or BH4 synthesis was found.

Is a little sunshine all we need? On the impact of sunshine regulation on profits, productivity and prices in the Dutch drinking water sector

This paper analyzes the performance of Dutch drinking water utilities before and after the introduction of sunshine regulation, which involves publication of the performance of utilities but no formal price regulation. By decomposing profit change into its economic drivers, our results suggest that, in the Dutch political and institutional context, sunshine regulation was effective in improving the productivity of publicly organised services. Nevertheless, while sunshine regulation did bring about a moderate reduction in water prices, sustained and substantial economic profits suggest that it may not have the potential to fully align output prices with economic costs in the long run. In methodological terms, the DEA based profit decomposition is extended to robust and conditional non-parametric efficiency measures, so as to account better for both uncertainty and differences in operating environment between utilities.

Nondestructive measurement of water content and moisture migration of unsaturated red clays in South China

To reveal the moisture migration mechanism of the unsaturated red clays, which are sensitive to water content change and widely distributed in South China, and then rationally use them as a filling material for highway embankments, a method to measure the water content of red clay cylinders using X-ray computed tomography (CT) was proposed and verified. Then, studies on the moisture migrations in the red clays under the rainfall and ground water level were performed at different degrees of compaction. The results show that the relationship between dry density, water content, and CT value determined from X-ray CT tests can be used to nondestructively measure the water content of red clay cylinders at different migration time, which avoids the error reduced by the sample-to-sample variation. The rainfall, ground water level, and degree of compaction are factors that can significantly affect the moisture migration distance and migration rate. Some techniques, such as lowering groundwater table and increasing degree of compaction of the red clays, can be used to prevent or delay the moisture migration in highway embankments filled with red clays.