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At least 19 recordsLinked to original sources
PubMed2025

Inclusion of Physical-Chemical Water Quality Measurements Can Improve Associations between SARS-CoV-2 RNA Levels in Wastewater and COVID-19 Cases within Smaller Sewersheds.

Measurements of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in wastewater can be used to understand the prevalence of COVID-19 cases within a community. Environmental conditions inclusive of physical-chemical water quality characteristics are known to impact wastewater SARS-CoV-2 signals, but they are rarely measured within the sewer infrastructure in areas upstream of wastewater treatment plants (WWTPs). The objectives of this study were to report on measurements of environmental parameters [flow and physical-chemical water quality (water temperature, pH, specific conductivity, dissolved oxygen, and turbidity)] upstream of a WWTP and to evaluate whether the inclusion of these environmental parameters improves correlations between SARS-CoV-2 RNA levels in wastewater, and COVID-19 prevalence in the sewershed community. Measurements of environmental parameters and SARS-CoV-2 RNA in wastewater spanned different time scales (minutes, hours and weeks) and population scales (building, campus, community). For short time scales, water quality parameters did not improve correlations between SARS-CoV-2 in wastewater and COVID-19 prevalence due to high variability of water quality and flows within the sewer system. When averaging data over weekly time scales, regressions showed that inclusion of pH improved correlations between RNA and COVID-19 prevalence. At the cluster scale, for the entire data set, the root mean square error decreased from 6.9 cases per week to 6.5 cases per week. At the community scale benefits were observed only for the delta wave with a decrease in root mean square error from 539 cases per week to 430 cases per week. The inclusion of pH improved correlations between wastewater SARS-CoV-2 and COVID-19 prevalence more frequently when evaluating the cluster sewershed scale (populations of a few thousand) in comparison to the community scale (populations of several 100,000). Given the simplicity of measuring pH and other physical-chemical water quality parameters, their inclusion should be considered as part of wastewater-based epidemiology programs.

COVID-19↗
PubMed1975

Potable water quality in rural Georgetown County.

Drinking water supplies of 161 rural communities, in Georgetown County, South Carolina, were randomly selected for sample collection. The analysis showed that most of the waters were slightly acidic. Low, but acceptable concentrations of chloride, copper, fluoride, sodium, cadmium, nitrate and phosphate were found. A few water samples showed higher then recommended levels of arsenic, mercury, zinc and lead. Although only 2% of the samples exceeded the mandatory limit of 0.05 ppm for arsenic, 72% exceeded the recommended level of 0.01 ppm. The mandatory limit for manganese was exceeded in 37% of the waters while 88% exceeded the limit for iron. The high iron content was generally responsible for the high turbidity found in 45% of the samples. The well depth and the consumer income had some bearing on water quality. Statistical evidence suggested that septic tank seepage was partially responsible for nitrate, phosphate, iron and arsenic contamination of shallow water supplies. Lead concentrations appear to vary according to the plumbing used and the pH of the waters.

Hydrogen-Ion Concentration↗
PubMed1979

Drinking water quality and sudden death: observations from West and East Finland.

Relationships of drinking water quality to CHD and sudden death were studied in two rural areas in western and eastern Finland. In the eastern area, drinking water is particularly soft and contains less magnesium and chromium but more copper than in the western area. A 15-year follow-up of resident males showed a higher death rate from CHD in the eastern area but no difference in the proportion of sudden deaths. The data suggest that CHD may be associated with low concentrations of magnesium and chromium in the drinking water, but no definite relationship was found between water quality and sudden death.

Chromium↗
PubMed1979

An experimental approach to the determinants of biological water quality.

A case is presented for the use of experimental bioassay techniques to detect and measure variations in water quality in the marine environment by exposing suitable organisms in the laboratory to water samples collected in the field. A technique is described which was developed for this purpose with the use of a clonal hydroid; preliminary results from Swansea Bay show that it is sensitive to the variations in water quality that occur there. Chemical techniques are being developed for use in conjunction with such bioassays to identify the kinds of contaminants responsible for a detected effect, and some preliminary experiments suggest that divalent metals and the volatile constituents of hydrocarbons can be removed selectively from sea water.

Animals↗
PubMedDate not supplied

[Studies on the water quality of the river Po and its tributaries between Monte Cremona and Casalmaggiore. II. Period 1971-2].

The results relating to the research carried out on the river Po upstream and downstream Cremona town, at Casalmaggiore and at the mouths of the right side tributaries Arda-Ongina and Taro in the period 1971-72 are reported in the present note. The samplings took place once every month and on the same day flow measurements were effected by the Magistracy of the river Po in the five stations. The results of this first series of sampling have shown a good stability of the water quality of the river Po, in the different seasons and in the different hydrological conditions. No significative differences were poi nted out for the most part of the determined parameters between the stations upstream and downstream Cremona and Casalmaggiore, except the turbid load (turbidity, suspended matter at 105 degrees C, setteable solids) which presented at Casalmaggiore an average value absolutely higher than the calculated one which was achieved considering concentrations and river flow at Cremona and at the mouths of Arda-Ongina and Taro. With few exceptions the water quality keeps a good level for fish life and its actual pollution degree let us think it possible to improve the situation in a short time. Only microbiological parameters are excepted, as they exceed the proposed limits for recreation and bathing uses (W.Q.C.).

Chlorides↗
PubMed1979

[Biological monitoring of water quality].

The degree of purity of surface waters can be seen from investigations on the communities of life of plant and animal organisms. A great number of organisms characteristic of certain degrees of pollution were classified in the "saprobic system", which is still valid. As a supplement to the chemical water analysis, the bio-ecological test is an optional method for characterizing the quality of waters--as, for instance, in the case of the river Lippe.

Animals↗
PubMed1977

Further aspects of a Markovian sampling policy for water quality monitoring.

In this paper, a Markov process is developed as a mathematical model to study the general problem of quality control monitoring. This approach was previously used by Arnold (1970) in development of sampling plans to study the water quality monitoring of streams. Arnold considered the expected sample size required for various sampling plans. Thre present authors have extended Arnold's work and derived equations for the variance of the sample size. In addition, approximation schemes are developed that could greatly enhance the implementation of this sampling procedure. Techniques are presented showing that an accurate approximation to the expected sample size can be obtained simply by the use of a hand calculator and equations developed within the paper. Moreover, accurate approximations for the variances of sample size can easily be obtained.

Quality Control↗
PubMedDate not supplied

[Researches on the water quality of the river Po and its tributaries between Cremona and Casalmaggiore. I. materials and methods (author's transl)].

During 1971 a research program about the status of pollution of the river Po and its tributaries was started by six Institutes of Hygiene altogether (Turin, Pavia, Milan, Parma, Modena and Ferrara Universities) with the Institute for Water Research of C.N.R. and Hydrographic Office of Magistracy of the Po. The role of the Parma University Hygiene Institute was to study the water qualities of the river Po between Cremona and Casalmaggiore and of two right side tributaries, Arda-Ongina and Taro. The hydrogeographical characteristics of the examined reach are reported in the present note, with special reference to the hydrological conditions, basin area, inhabitants and industrial typology. The sampling stations were placed upstream and downstream Cremona town, near Casalmaggiore and at the mouth of Arda-Ongina and Taro. Moreover the methods, for chemical and bacteriological analysis are reported.

Clostridium perfringens↗