Daily Archives: October 13, 2012

Human adenoviruses detected in environmental samples

Y. Dong, J. Kim and G.D. Lewis. Evaluation of methodology for detection of human adenoviruses in wastewater, drinking water, stream water and recreational waters. Journal of Applied Microbiology. 108 (2020) 800-809.

Abstract: This study evaluates dialysis filtration and a range of PCR detection methods for identification and quantification of human adenoviruses in a range of environmental waters.

Methods and Results: Adenovirus was concentrated from large volumes (50–200 l) of environmental and potable water by hollow fibre microfiltration using commercial dialysis filters. By this method, an acceptable recovery of a seeded control bacteriophage MS2 from seawater (median 95.5%, range 36–98%, n-5) and storm water (median 84.7%, range 23–94%, n = 5) and storm water (median 59.5%, range 63–112%, n = 5) was achieved. Adenovirus detection using integrated cell culture PCR (ICC-PCR), direct PCR, nested PCR, real-time quantitative PCR (qPCR) and adenovirus group F-specific direct PCR was tested with PCR products sequenced for confirmation. Adenovirus was routinely detected from all water types by most methods, with ICC-PCR more sensitive than direct-nested PCR or qPCR. Group F adenovirus dominated in wastewater samples but was detected very infrequently in environmental waters.

Conclusions and Implications: Human adenoviruses (HAdv) proved relatively common in environmental and potable waters when assessed using an efficient concentration method and sensitive detection method. ICC-PCR proved most sensitive, could be used semiquantitatively and demonstrated virus infectivity but was time consuming and expensive. qPCR provided quantitative results but was ten-fold less sensitive than the best methods.

Cyanobacteria and cyanotoxin treatment methods…

Judy A. Westrick, David C. Szlag, Benjamin J. Southwell, James Sinclair. A review of cyanobacteria and cyanotoxins removal/inactivation in drinking water treatment. Anal Bioanal Chem (2010) 397:1705. DOI 10.1007/s00216-010-3709-5

Abstract: This review focuses on the efficiency of different water treatment processes for the removal of cyanotoxins from potable water. Although several investigators have studied full-scale drinking water processes to determine the efficiency of cyanotoxin inactivation, many of the studies were based on ancillary practice. In this context, practice refers to the removal or inactivation of cyanotoxins by standard daily operational procedures and without a contingency operational plan utilizing specific treatment barriers. In this review, auxiliary practice refers to the implementation of inactivation/removal treatment barriers or operational changes explicitly designed to minimize risk from toxin-forming algae and their toxins to make potable water. Furthermore, the best drinking water treatment practices are based on extension of the multibarrier approach to remove cyanotoxins from water. Cyanotoxins are considered natural contaminants that occur worldwide and specific classes of cyanotoxins have shown regional prevalence. For example, freshwaters in the Americas often show high concentrations of microcystin, anatoxin-a, and cylindrospermopsin, whereas Australian water sources often show high concentrations of microcystin, cylindrospermopsin, and saxitoxins. Other less frequently reported cyanotoxins include lyngbyatoxin A, debromoaplysiatoxin, and B-N-methylamino-L-alanine. This review focuses on the commonly used unit processes and treatment trains to reduce the toxicity of four classes of cyanotoxins: the microcystins, cylindrospermopsin, anatoxin-a, and saxitoxins. The goal of this review is to inform the reader of how each unit process participates in a treatment train and how an auxiliary multibarrier approach to water treatment can provide safer water for the consumer.

Click here for the full paper (free).


North Carolina farm camps have substandard drinking water

Werner E. Bischoff, Maria Weir, Phillip Summers, Haiying Chen, Sara A. Quandt, Amy K. Liebman, and Thomas A. Arcury. The Quality of Drinking Water in North Carolina Farmworker Camps. Am J Public Health. 2012;102: e49–e54. doi:10.2105/AJPH.2012.300738

Objectives. The purpose of this study was to assess water quality in migrant farmworker camps in North Carolina and determine associations of water quality with migrant farmworker housing characteristics.

Methods. We collected data from 181 farmworker camps in eastern North Carolina during the 2010 agricultural season. Water samples were tested using the Total Coliform Rule (TCR) and housing characteristics were assessed using North Carolina Department of Labor standards.

Results. A total of 61 (34%) of 181 camps failed the TCR. Total coliform bacteria
were found in all 61 camps, with Escherichia coli also being detected in 2. Water
quality was not associated with farmworker housing characteristics or with access to registered public water supplies. Multiple official violations of water quality standards had been reported for the registered public water supplies.

Conclusions. Water supplied to farmworker camps often does not comply with
current standards and poses a great risk to the physical health of farmworkers
and surrounding communities. Expansion of water monitoring to more camps and changes to the regulations such as testing during occupancy and stronger enforcement are needed to secure water safety.

No adverse effects of perchlorate observed in California newborns

Patricia A. Buffler, Michael A. Kelsh, Edmund C. Lau, Charlotte H. Edinboro, Julie C. Barnard, George W. Rutherford, Jorge J. Daaboul, Lynn Palmer, and Fred W. Lorey.  Thyroid Function and Perchlorate in Drinking Water: An Evaluation among California Newborns, 1998. Environmental Health Perspectives, Vol. 114, No. 5, May 2006. doi:10.1289/ehp.8176

Abstract: Perchlorate (ClO4-) has been detected in groundwater sources in numerous communities in California and other parts of the United States, raising concerns about potential impacts on health. For California communities where ClO4- was tested in 1997 and 1998, we evaluated the prevalence of primary congenital hypothyroidism (PCH) and high thyroid-stimulating hormone (TSH) levels among the 342,257 California newborns screened in 1998. We compared thyroid function results among newborns from 24 communities with average ClO4- concentrations in drinking water > 5 μg/L (n = 50,326) to newborns from 287 communities with average concentrations ≤ 5 μg/L (n = 291,931). ClO4- concentrations obtained from the California Drinking Water Program provided source-specific data for estimating weighted average concentrations in community water. Fifteen cases of PCH from communities with average concentration > 5 μg/L were observed, with 20.4 expected [adjusted prevalence odds ratio (POR) = 0.71; 95% confidence interval(CI), 0.40–1.19]. Although only 36% of all California newborns were screened before 24 hr of age in 1998, nearly 80% of newborns with high TSH were screened before 24 hr of age. Because of the physiologic postnatal surge of TSH, the results for newborns screened before 24 hr were uninformative for assessing an environmental impact. For newborns screened ≥ 24 hr, the adjusted POR for high TSH was 0.73 (95% CI, 0.40–1.23). All adjusted odds ratios (ORs) were controlled for sex, ethnicity, birth weight, and multiple birth status. Using an assessment of ClO4- in drinking water based on available data, we did not observe an association between estimated average ClO4– concentrations > 5 μg/L in drinking water supplies and the prevalence of clinically diagnosed PCH or high TSH concentrations.