Tag Archives: Sweden

Global warming believer turns on himself


“These global warming people are crazy. First, they want to take away our juicy steaks because cows fart, but now…this crosses the line of decency.  A Swedish scientist suggests that it may be necessary to turn to cannibalism and start eating human flesh to save the planet (giving new meaning to the expression bite me) And NO this story is not from The Onion.” click here

Status of Small Water Systems in Nordic Countries

Gunnarsdottir MJ, Persson KM, Andradottir HO, Gardarsson SM. Status of small water supplies in the Nordic countries: Characteristics, water quality and challenges. International journal of hygiene and environmental health. 2017 Aug 24. pii: S1438-4639(17)30391-7. doi: 10.1016/j.ijheh.2017.08.006.

Access to safe water is essential for public health and is one of the most important prerequisites for good living and safe food production. Many studies have shown that non-compliance with drinking water quality standards in small water supply systems is much higher than in large systems. Nevertheless, people served by small water supply systems have the right to the same level of health protection. Actions are therefore needed to improve the situation. The objective of the present study was to carry out a baseline analysis of the situation in the Nordic region and provide recommendations for governmental policy and actions. Data were gathered on number of water supplies, population served, compliance with regulations and waterborne disease outbreaks from various sources in the Nordic countries. The collected data showed that there are about 12500 regulated water supplies, 9400 of which serve fewer than 500 persons. The number of unregulated and poorly regulated supplies is unknown, but it can be roughly estimated that these serve 10% of the Nordic population on a permanent basis or 2.6 million people. However, this does not tell the whole story as many of the very small water supplies serve transient populations, summerhouse dwellers and tourist sites, with many more users. Non-compliance regarding microbes is much higher in the small supplies. The population weighted average fecal contamination incidence rate in the Nordic region is eleven times higher in the smaller supplies than in the large ones, 0.76% and 0.07%, respectively. Registered waterborne disease outbreaks were also more frequent in the small supplies than in the large ones.

Coronary Heart Disease in Sweden not Associated with Fluoride?

This type of study design can indicate whether a forest fire is burning but not whether there are smoldering embers in the forest causing other types of damage. In such a large population even a small effect could theoretically be identified but exposure assessment and misclassification confound the results. All things considered the study does not offer much evidence one way (effect) or the other (no effect). The assumptions made by the researchers going into the study define the resulting conclusion.

Interesting how “negative” studies on fluoride such as this are published while “negative” studies showing little or no benefits to communal fluoridation are not published.  This is the classic publication bias whether intended or unintended. 

Peggy Näsman, Fredrik Granath, Jan Ekstrand, Anders Ekbom, Gunilla Sandborgh-Englund, C. Michael Fored. Natural fluoride in drinking water and myocardial infarction: A cohort study in Sweden. Science of The Total Environment, Volume 562, 15 August 2016, Pages 305-311.

Large geographical variation in the coronary heart disease (CHD) incidence is seen worldwide and only a part of this difference is attributed to the classic risk factors. Several environmental factors, such as trace elements in the drinking water have been implicated in the pathogenesis of CHD. The objective was to assess the association between drinking water fluoride exposure and myocardial infarction in Sweden using nationwide registers. This large cohort consisted of 455,619 individuals, born in Sweden between January 1, 1900 and December 31, 1919, alive and living in their municipality of birth at the time of start of follow-up. Estimated individual drinking water fluoride exposure was stratified into four categories: very low (< 0.3 mg/l), low (0.3–<0.7 mg/l), medium (0.7–<1.5 mg/l) and high (≥ 1.5 mg/l). In Cox regression analyses, compared to the very low fluoride group, the adjusted Hazard Ratio for the low fluoride group was 0.99 (95% confidence interval, 0.98–1.00), for the medium fluoride group 1.01 (95% confidence interval, 0.99–1.03) and 0.98 (95% confidence interval, 0.96–1.01) for the highest fluoride group. Adding water hardness to the model did not change the results. We conclude that the investigated levels of natural drinking water fluoride content does not appear to be associated with myocardial infarction, nor related to the geographic myocardial infarction risk variation in Sweden. Potential misclassification of exposure and unmeasured confounding may have influenced the results.

Water Fluoridation and Bone Fracture Risk

It seems that these researchers may not be fully aware of how assumptions drive if not determine their conclusions. 

P. Näsman, J. Ekstrand, F. Granath, A. Ekbom, C.M. Fored. Estimated Drinking Water Fluoride Exposure and Risk of Hip Fracture: A Cohort Study. Journal of Dental Research, Nov 2013; 92(11): 1029-1034.

The cariostatic benefit from water fluoridation is indisputable, but the knowledge of possible adverse effects on bone and fracture risk due to fluoride exposure is ambiguous. The association between long-term (chronic) drinking water fluoride exposure and hip fracture (ICD-7-9: ‘820’ and ICD-10: ‘S72.0-S72.2’) was assessed in Sweden using nationwide registers. All individuals born in Sweden between January 1, 1900 and December 31, 1919, alive and living in their municipality of birth at the time of start of follow-up, were eligible for this study. Information on the study population (n = 473,277) was linked among the Swedish National In-Patient Register (IPR), the Swedish Cause of Death Register, and the Register of Population and Population Changes. Estimated individual drinking water fluoride exposure was stratified into 4 categories: very low, < 0.3 mg/L; low, 0.3 to 0.69 mg/L; medium, 0.7 to 1.49 mg/L; and high, ≥ 1.5 mg/L. Overall, we found no association between chronic fluoride exposure and the occurrence of hip fracture. The risk estimates did not change in analyses restricted to only low-trauma osteoporotic hip fractures. Chronic fluoride exposure from drinking water does not seem to have any important effects on the risk of hip fracture, in the investigated exposure range.

Hollow-Fiber Nanofiltration for Improved Organics Removal

Köhler SJ, Lavonen E, Keucken A, Schmitt-Kopplin P, Spanjer T, Persson K. Upgrading coagulation with hollow-fibre nanofiltration for improved organic matter removal during surface water treatment. Water Research 2015 Nov 27;89:232-240. doi: 10.1016/j.watres.2015.11.048.

Rising organic matter concentrations in surface waters in many Nordic countries require current drinking water treatment processes to be adapted. Accordingly, the use of a novel nanofiltration (NF) membrane was studied during a nine month period in pilot scale at a large drinking water treatment plant in Stockholm, Sweden. A chemically resistant hollow-fibre NF membrane was fed with full scale process water from a rapid sand filter after aluminum sulfate coagulation. The combined coagulation and NF process removed more than 90% of the incoming lake water dissolved organic carbon (DOC) (8.7 mg C L-1), and 96% of the absorbance at 254 nm (A254) (0.28 cm-1 incoming absorbance). Including granulated active carbon GAC) filter, the complete pilot plant treatment process we observed decreases in DOC concentration (8.7-0.5 mg C L-1), SUVA (3.1-1.7 mg-1 L m-1), and the average nominal molecular mass (670-440 Da). Meanwhile, water hardness was practically unaffected (<20% reduction). Humic substances (HS) and biopolymers were almost completely eliminated (6510-140 and 260 to 10 μg C L-1 respectively) and low molecular weight (LMW) neutrals decreased substantially (880-190 μg C L-1). Differential excitation emission matrices (EEMs), which illustrate the removal of fluorescing organic matter (FDOM) over a range of excitation and emission wavelengths, demonstrate that coagulation removed 35 ± 2% of protein-like material and 65 ± 2% of longer emission wavelength, humic-like FDOM. The subsequent NF treatment was somewhat less selective but still preferentially targeted humic-like FDOM (83 ± 1%) to a larger extent than protein-like material (66 ± 3%). The high selectivity of organic matter during coagulation compared to NF separation was confirmed from analyses with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), and liquid chromatography with organic carbon detection (LC-OCD), as coagulation exclusively targeted oxidized organic matter components while NF removed both chemically reduced and oxidized components. DOC removal and change in DOC character in the GAC filters showed marked differences with slower saturation and more pronounced shifts in DOC character using NF as pre-treatment. Fluorescence derived parameters showed a similar decrease over time of GAC performance for the first 150 days but also indicated ongoing change of DOM character in the post NF GAC filtrate over time even after LC-OCD indicated steady state with respect to outgoing carbon. During our trial iron concentrations were low (<30 ppb) and thus A254 could be directly related to the concentration of HS (R2 = 0.9). The fluorescence derived freshness index (β:α) proved to be an excellent variable for estimating the fraction of HS present in all samples. Given the recommended limit of 4 mg L−1 for chemical oxygen demand (COD) for Swedish drinking water, coagulation will need to be supplemented with one or more treatment steps irrespective whether climate change will lead to drier or wetter conditions in order to maintain sufficient DOC removal with the current increasing concentrations in raw waters.

PFAA Contamination of Drinking Water, Sweden

Gyllenhammar I, Berger U, Sundström M, McCleaf P, Eurén K, Eriksson S, Ahlgren S, Lignell S, Aune M, Kotova N, Glynn A. Influence of contaminated drinking water on perfluoroalkyl acid levels in human serum – A case study from Uppsala, Sweden. Environmental Research. 2015 Jun 12;140:673-683. doi: 10.1016/j.envres.2015.05.019.

In 2012 a contamination of drinking water with perfluoroalkyl acids (PFAAs) was uncovered in the City of Uppsala, Sweden. The aim of the present study was to determine how these substances have been distributed from the contamination source through the groundwater to the drinking water and how the drinking water exposure has influenced the levels of PFAAs in humans over time. The results show that PFAA levels in groundwater measured 2012-2014 decreased downstream from the point source, although high ΣPFAA levels (>100ng/L) were still found several kilometers from the point source in the Uppsala aquifer. The usage of aqueous film forming fire-fighting foams (AFFF) at a military airport in the north of the city is probably an important contamination source. Computer simulation of the distribution of PFAA-contaminated drinking water throughout the City using a hydraulic model of the pipeline network suggested that consumers in the western and southern parts of Uppsala have received most of the contaminated drinking water. PFAA levels in blood serum from 297 young women from Uppsala County, Sweden, sampled during 1996-1999 and 2008-2011 were analyzed. Significantly higher concentrations of perfluorobutane sulfonic acid (PFBS) and perfluorohexane sulfonic acid (PFHxS) were found among women who lived in districts modeled to have received contaminated drinking water compared to unaffected districts both in 1996-1999 and 2008-2011, indicating that the contamination was already present in the late 1990s. Isomer-specific analysis of PFHxS in serum showed that women in districts with contaminated drinking water also had an increased percentage of branched isomers. Our results further indicate that exposure via contaminated drinking water was the driving factor behind the earlier reported increasing temporal trends of PFBS and PFHxS in blood serum from young women in Uppsala.

Color, Iron, and Organic Carbon in Swedish Watercourses

Temnerud J, Hytteborn JK, Futter MN, Köhler SJ. Evaluating common drivers for color, iron and organic carbon in Swedish watercourses. Ambio. 2014 Dec;43 Suppl 1:30-44. doi: 10.1007/s13280-014-0560-5.

The recent browning (increase in color) of surface waters across much of the northern hemisphere has important implications for light climate, ecosystem functioning, and drinking water treatability. Using log-linear regressions and long-term (6-21 years) data from 112 Swedish watercourses, we identified temporal and spatial patterns in browning-related parameters [iron, absorbance, and total organic carbon (TOC)]. Flow variability and lakes in the catchment were major influences on all parameters. Co-variation between seasonal, discharge-related, and trend effects on iron, TOC, and absorbance were dependent on pH, landscape position, catchment size, latitude, and dominant land cover. Large agriculture-dominated catchments had significantly larger trends in iron, TOC, and water color than small forest catchments. Our results suggest that while similarities exist, no single mechanism can explain the observed browning but show that multiple mechanisms related to land cover, climate, and acidification history are responsible for the ongoing browning of surface waters.

Click here for paper (Open Access).