O’Neill K, Musgrave IF, Humpage A. Low dose extended exposure to saxitoxin and its potential neurodevelopmental effects: A review.
Environ Toxicol Pharmacol. 2016 Sep 28;48:7-16. doi: 10.1016/j.etap.2016.09.020.
Saxitoxin (STX) and its analogs, the paralytic shellfish toxins (PSTs), are a group of potent neurotoxins well known for their role in acute paralytic poisoning by preventing the generation of action potentials in neuronal cells. They are found in both marine and freshwater environments globally and although acute exposure from the former has previously received more attention, low dose extended exposure from both sources is possible and to date has not been investigated. Given the known role of cellular electrical activity in neurodevelopment this pattern of exposure may be a significant public health concern. Additionally, the presence of PSTs is likely to be an ongoing and possibly increasing problem in the future. This review examines the neurodevelopmental toxicity of STX, the risk of extended or repeated exposure to doses with neurodevelopmental effects, the potential implications of this exposure and briefly, the steps taken and difficulties faced in preventing exposure.
Goovaerts P. The drinking water contamination crisis in Flint: Modeling temporal trends of lead level since returning to Detroit water system. The Science of the total environment. 2016 Oct 5. pii: S0048-9697(16)32137-4. doi: 10.1016/j.scitotenv.2016.09.207.
Since Flint returned to its pre-crisis source of drinking water close to 25,000 water samples have been collected and tested for lead and copper in >10,000 residences. This paper presents the first analysis and time trend modeling of lead data, providing new insights about the impact of this intervention. The analysis started with geocoding all water lead levels (WLL) measured during an 11-month period following the return to the Detroit water supply. Each data was allocated to the corresponding tax parcel unit and linked to secondary datasets, such as the composition of service lines, year built, or census tract poverty level. Only data collected on residential parcels within the City limits were used in the analysis. One key feature of Flint data is their collection through two different sampling initiatives: (i) voluntary or homeowner-driven sampling whereby concerned citizens decided to acquire a testing kit and conduct sampling on their own (non-sentinel sites), and (ii) State-controlled sampling where data were collected bi-weekly at selected sites after training of residents by technical teams (sentinel sites). Temporal trends modeled from these two datasets were found to be statistically different with fewer sentinel data exceeding WLL thresholds ranging from 10 to 50μg/L. Even after adjusting for housing characteristics the odds ratio (OR) of measuring WLL above 15μg/L at non-sentinel sites is significantly >1 (OR=1.480) and it increases with the threshold (OR=2.055 for 50μg/L). Joinpoint regression showed that the city-wide percentage of WLL data above 15μg/L displayed four successive trends since the return to Detroit Water System. Despite the recent improvement in water quality, the culprit for differences between sampling programs needs to be identified as it impacts exposure assessment and might influence whether there is compliance or not with the Lead and Copper Rule.
Posted in Lead
Tagged Lead, Michigan
“In yet another stunning blow to the #ExxonKnew campaign, a federal judge today issued a discovery order against Massachusetts Attorney General Maura Healey to determine whether “bias or prejudgment” influenced her decision to initiate a “bad faith” investigation into ExxonMobil, just days after she appeared before news cameras with New York Attorney General Eric Schneiderman, Al Gore and other Democratic state attorneys general in New York.” click here
“But there are a few glaring problems with Clinton’s premise that Hurricane Matthew was actually worse because of “climate change” – the first and most obvious being the question, worse than what? There was no bare-minimum destruction standard for Matthew, or any other hurricane for that matter. It was what it was, and any one of a million different variables could have caused it to turn out differently. This wild assumption of a statement may seek to carry emotional weight to influence voters, but it’s heavily lacking in factual evidence.” click here
“Experts say California is in a permanent drought, caused by global warming and disappearing Arctic ice.
Precipitation there was above normal over the past 12 months, and there has been no trend over the past 120 years.” click here
Gunnarsdottir MJ, Gardarsson SM, Jonsson GS, Bartram J.Chemical quality and regulatory compliance of drinking water in Iceland. Int J Hyg Environ Health. 2016 Sep 26. pii: S1438-4639(16)30175-4. doi: 10.1016/j.ijheh.2016.09.011.
Assuring sufficient quality of drinking water is of great importance for public wellbeing and prosperity. Nations have developed regulatory system with the aim of providing drinking water of sufficient quality and to minimize the risk of contamination of the water supply in the first place. In this study the chemical quality of Icelandic drinking water was evaluated by systematically analyzing results from audit monitoring where 53 parameters were assessed for 345 samples from 79 aquifers, serving 74 water supply systems. Compliance to the Icelandic Drinking Water Regulation (IDWR) was evaluated with regard to parametric values, minimum requirement of sampling, and limit of detection. Water quality compliance was divided according to health-related chemicals and indicators, and analyzed according to size. Samples from few individual locations were benchmarked against natural background levels (NBLs) in order to identify potential pollution sources. The results show that drinking compliance was 99.97% in health-related chemicals and 99.44% in indicator parameters indicating that Icelandic groundwater abstracted for drinking water supply is generally of high quality with no expected health risks. In 10 water supply systems, of the 74 tested, there was an indication of anthropogenic chemical pollution, either at the source or in the network, and in another 6 water supplies there was a need to improve the water intake to prevent surface water intrusion. Benchmarking against the NBLs proved to be useful in tracing potential pollution sources, providing a useful tool for identifying pollution at an early stage.
Fakhr AE, Gohar MK, Atta AH. Impact of Some Ecological Factors on Fecal Contamination of Drinking Water by Diarrheagenic Antibiotic-Resistant Escherichia coli in Zagazig City, Egypt. International journal of microbiology. 2016;2016:6240703.
Fecal contamination of drinking water is a major health problem which accounts for many cases of diarrhea mainly in infants and foreigners. This contamination is a complex interaction of many parameters. Antibiotic resistance among bacterial isolates complicates the problem. The study was done to identify fecal contamination of drinking water by Diarrheagenic Antibiotic-Resistant Escherichia coli in Zagazig city and to trace reasons for such contamination, three hundred potable water samples were investigated for E. coli existence. Locations of E. coli positive samples were investigated in relation to population density, water source, and type of water pipe. Sixteen E. coli strains were isolated. Antibiotic sensitivity was done and enterotoxigenic, enteropathogenic, and enterohaemorrhagic virulence genes were investigated by PCR. Probability of fecal contamination correlated with higher population density, with increased distance from Zagazig water plant, and with asbestos cement in all isolates. Virulence genes were detected in a rate of 26.27%, 13.13%, 20%, 6.67%, and 33.33% for LT, ST, stx1, stx2, and eae genes, respectively. This relatively high frequency of fecal contamination points towards the high risk of developing diarrhea by antibiotic resistant DEC in low socioeconomic communities particularly with old fashion distribution systems.