Authors: N. Gai, J. Pan, H. Tang, S. Chen, D. Chen, X. Zhu, G. Lu and Y. Yang
Source: Science of The Total Environment, Vol. 478, 2014
http://www.sciencedirect.com/science/article/pii/S0048969714000114
Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in surface soils along a transect from source areas (a petro-chemical industrial city, Lanzhou and its adjacent agricultural areas) to Ruoergai highland prairie (3552 m above sea level (a.s.l.)), where livestock farming was the only human economic activity, were studied. OCPs in Ruoergai soils were dominated by HCHs. The land types, organic carbon contents and pH affected the POP preservation in soil. OCPs and PCBs in surface soils in Ruoergai wetland and grassland showed different contamination patterns; OCP levels in wetland soils were higher than those in grassland. Significant correlations were observed between total organic carbon (TOC) contents and PCB concentrations in the soils. The land type determines TOC content in soils, which in turn was a major factor on soil concentrations of POPs. The transect was divided into two sections: The first section (Gradient I) is from Lanzhou (1740 m a.s.l.) to Luqu (2400 m a.s.l.) with decreasing agricultural activities, and the second section (Gradient II) is from Luqu to Ruoergai (3500 m a.s.l.) with grassland as the main land type. Soils of Ruoergai area were dominated by α-HCH, β-HCH, HCB, and PCB28, suggesting that the behaviors of POPs in the high plateau region were different from high mountain cold-trapping effect, and that the POPs' behaviors in high plateau region were similar to Polar Regions.
Title: Determination of Pesticides Residues in Brazilian Grape Juices Using GC-MS-SIM
Authors: A.A.R. Alves, A.S. Rodrigues, E.B.P. Barros, T.M. Uekane, H.R. Bizzo and C.M. Rezende
Source: Food Analytical Methods, 2014
http://link.springer.com/article/10.1007/s12161-014-9823-9
The production of grape juice in Brazil is growing at a 30 % rate a year. To increase exports, a full complainment to food safety protocols, as those in the Codex Alimentarius, is mandatory. Simple and fast analytical methods are needed for quality assurance. The objective of this work was to develop and validate an analytical method for detection of pesticides residues (organochlorides, organophosphorides, and fungicides) in Brazilian whole grape juices. The analyses were performed by gas chromatography coupled to mass spectrometry, operating in selective ion monitoring. After liquid–liquid extraction, samples were preconcentrate using solid-phase extraction in Florisil. The limit of quantification ranged from 3.75 to 9.47 mg l-1, and recovery varied from 84.0 % to 99.7 %, with RSD lower than 4.9 %. From a total of 99 Brazilian grape juices analyzed, pesticide residues were found in 32.
Title: Pesticides & male infertility: Harm from the womb through adulthood -- and into the next generation
Date: 26 February, 2014
Source: Physicians for Social Responsibility
http://www.psr.org/environment-and-health/environmental-health-policy-institute/responses/pesticides-and-male-infertility.html
Human reproduction is a delicate bio-chemical process, guided at every step by powerful hormones. Reproductive health involves everything from the physical ability to reproduce to the many behavioral and developmental effects of sex hormones.
This finely tuned system is under threat, and male fertility appears to be particularly at risk. Worldwide, sperm counts are down and infertility rates are up. The Association of Reproductive Health Professionals highlights concerning trends[i] in male reproductive health, including:
Rising rates of testicular cancer
Falling sperm counts
Decline in testosterone levels
Fewer males being born
Increases in certain types of birth defects
Science tells us that pesticides and other chemicals are at least partly to blame. Endocrine disrupting chemicals are particularly adept at interfering with reproductive health, even when exposure levels are extremely low. Some of these chemicals are structurally similar to human hormones, and can block (or put into overdrive) the body's natural system of biological signals.
An infant in the womb is particularly vulnerable to such disruption, as hormones are busy regulating the differentiation of cells and development of organs. Infants exposed to a triggering chemical just when the reproductive organs are forming — or the brain developing, or immune system coalescing — can experience harm that can play out over the course of a lifetime. The Endocrine Disruption Exchange has a compelling online tool[ii] illustrating the vulnerabilities of a fetus at various stages of development.
Scientists from the national Endocrine Society explain why the timing of exposure is so important:
...there are critical developmental periods during which there may be increased susceptibility to environmental endocrine disruptors. In those cases in which disruption is directed toward programming of a function, e.g., reproductive health, this may interfere with early life organization, followed by a latent period, after which the function becomes activated and the dysfunction can become obvious.[iii]
In other words, exposure to certain chemicals when an infant's reproductive system is developing can completely derail the process. But the effects won’t become evident until years later, when problems arise during puberty or when trying to conceive.
Adult exposures to pesticides can influence male fertility as well. Authors of a 2013 review published in Toxicology[iv] examined 17 studies published between 2007 and 2012, all exploring how environmental and occupational exposures to pesticides affect semen quality. Some studies looked at individual chemicals (such as DDT and hexachlorocyclohexane), others looked at classes of pesticides such as organophosphates and pyrethroids. The majority of these studies (15 of the 17) found significant links between pesticide exposure and lower semen quality, with decreased sperm concentration the most commonly reported finding.
Links between pesticide exposure and damage to men's reproductive ability are hardly new. The classic example is Dow's fumigant Nemogen (DBCP), which sterilized workers both in the California factory where it was produced and in the Nicaraguan banana plantations[v] where it was heavily applied. And exposure to current-use pesticides like atrazine and diazinon[vi] has also been shown to undermine sperm viability and function.
Pesticides can damage the male reproductive system in a number of ways. Some chemicals can kill or damage cells; if these are sperm cells, infertility can result. Others alter DNA structure, causing gene mutations that may result in birth defects or an inability to conceive. And still others cause what are known as "epigenetic" effects, meaning they change the way genes are expressed.[vii]
It’s been known for some time that pollutants can strip or add chemical tags to DNA, locking the expression of these genes on or off and changing how they function. These changes are called “epigenetic tags,” and have been linked to various health effects including death of sperm-forming cells.
Perhaps most sobering of all, emerging science shows that these genetic changes can be passed from one generation to the next. Recent studies from Spain[viii] and Washington state[ix] found that exposure to some chemicals can override the genetic “reset button” designed to protect a developing fetus from such changes. These trans-generational effects give new urgency to efforts to reduce our use of and exposure to harmful pesticides.
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