Daily Archives: November 11, 2012

Water fluoridation not necessary for dental health

I ran across this figure, which looks a bit old now, but nevertheless supports the contention that adding fluoride to water is not necessary for dental health…

Utica (NY) citizen questions fluoride addition….

Fluoride addition is the sacred cow of the public health field….but citizens are starting to challenge the practice, as well they should.

Click here for more….

 

Milwaukee (WI): No reason to add fluoride

It will be very difficult for dentists to admit that it is not necessary to add fluoride for dental health. Especially in Wisconsin, where fluoride dentist activism began (and which has now moved to Florida).

This article was published earlier this year…..click here.

 

 

Aurora, Colorado climate study….believe it or not

Studies such as this are useful and necessary to help advance the science. But the results are predetermined by the assumptions brought in to the analysis. I will not take the time here to recite the limits of the study affecting its utility for decisionmaking….Such studies are not falsifiable within the scientific method…..so you either believe it or not.

E. Towler, B. Raucher, R. Balaji, R. Alfredo, D. Yates, and R. Summers.  Incorporating Climate Uncertainty in a Cost Assessment for New Municipal Source Water. Journal of Water Resources Planning and Management; Sep2011, Vol. 138 Issue 5, p396-402.

Though new water supply source development has always required planning under many forms of uncertainty, climate change presents an added dimension that may exacerbate supply and water quality challenges. Hence, new decision-support tools are needed, and in this paper an approach that incorporates the uncertainty of climate variability and change into a cost assessment framework for a municipal drinking water provider in Colorado is developed and applied. The water utility provider is developing a new source of water supply, but treatment costs are relatively high because of the advanced processes needed to treat the water to desired standards. Furthermore, the new water source has variable salinity concentrations that are not removed by any of the implemented treatment processes, requiring blending with an existing lower salinity water source. This results in an increase in the finished water salinity (as compared with the existing water source), which can have negative impacts on customer satisfaction and the life span of water-using appliances. To plan for the development of this water supply source, an approach is proposed to assess the potential treatment and residential costs associated with the blending of the new water source with an existing source under climate uncertainty. Uncertainty from climate variability is captured through a previously developed stochastic streamflow and water quality simulation method that utilizes climate change scenarios. Results show that the proposed blend strategies incur increased treatment costs and economic impacts for customers. Specifically, a 30% reduction in annual flows from climate change translates into a 12% treatment cost increase and a 22% rise in residential costs.

Fluoride bioaccumulates in the aquatic environment

S. Del Piero, L. Masiero, S. Carellato. Influence of temperature on fluoride toxicity and bioaccumulation in the nonindigenous freshwater mollusk Dreissena polymorpha Pallas, 1769. Environ. Toxicol. Chem. 2012; 31: 2567-2571.

Fluoride toxicity and bioaccumulation tests (short- and long-term) were performed on the nonindigenous freshwater mollusk Dreissena polymorpha at two different temperatures: 17 ± 0.5°C and 22 ± 0.5°C. Concentrations that did not result in toxicity in short-term experiments (96 h) induced effects over a longer period (17 weeks), especially at the warmest temperature, highlighting the role of this parameter. Fluoride bioaccumulation increased linearly with increasing concentration and temperature, reaching 4,202 µg F/g dry weight in soft tissues only after 48 h of exposure at 22°C at a concentration of 640 mg F/L. Comparing tolerance to fluoride and bioaccumulation values of this species with those of other freshwater invertebrates, D. polymorpha was much more resistant and revealed its capacity to accumulate a great quantity of this xenobiotic substance. The results of the present study demonstrated that fluoride accumulation in the soft tissue of this animal was much higher (up to 1,409.6 µg F/g dry wt) than that in its shell (up to 706.4 µg F/g dry wt). If we consider this datum and the fact that D. polymorpha is widespread in many aquatic ecosystems around the world, representing a food source for many birds and other vertebrates, we must acknowledge the possibility that it can represent a serious danger in view of fluoride biomagnification in the aquatic environment.