| Bethells spraying effects Community |
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| By Steffan Browning |
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The intended helicopter spraying of crack willow with herbicide over 23 ha of wetland at Te Henga, near Bethells Beach, is another example of New Zealand’s use of crude chemical solutions without deep understanding of environmental risks, according to the Soil & Health Association of NZ. The Soil & Health Association of NZ Pesticide Action Network Aotearoa New Zealand (1) http://www.waitakere.govt.nz/cnlser/pw/greennetwk/tehengawetland....asp Recently scientists have found harmful effects on human cells at levels of glyphosate too low to have a herbicidal effect, some at levels similar to those found in food. These effects are amplified by the adjuvants in the Roundup formulation, which assist penetration of the cells by glyphosate. Several researchers have reported that glyphosate appears to accumulate in human cells. Cancer, genotoxicity, endocrine disruption, reproduction The International Programme on Chemical Safety (IPCS) and the United States Environmental Protection Agency (US EPA) have declared that glyphosate is not carcinogenic to humans. The US EPA originally classified glyphosate as a Group C 'possible human carcinogen', then re-classified it as Group D 'not classifiable as to human carcinogenicity', then as Group E 'evidence of non-carcinogenicity in humans', and then in 2006 rephrased this as 'Group E carcinogen with no evidence of human carcinogenicity'. Yet there is substantial laboratory and some epidemiological evidence that points to the opposite conclusion. Some researchers have concluded that glyphosate and its formulations clearly present a risk of carcinogenic, mutagenic, and reproductive effects on human cells. Numerous laboratory studies have shown that glyphosate and the Roundup formulation can be genotoxic and endocrine disrupting. One study summarises these effects occurring at doses substantially lower than those used in agriculture, or permitted as residues: at 0.5 mg/kg (40 times lower than levels permitted in soybeans in the US) they were anti-androgenic; at 2 mg/kg they were anti-oestrogenic; at 1 mg/kg they disrupted the enzyme aromatase; at 5 mg/kg they damaged DNA, and at 10 mg/kg there were cytotoxic. These effects can result in crucial outcomes for sexual and other cell differentiation, bone metabolism, liver metabolism, reproduction, development and behaviour, and hormone dependent diseases such as breast and prostate cancer (Gasnier et al 2009). Studies have demonstrated that glyphosate and/or Roundup cause genetic damage in human lymphocytes and liver cells; bovine lymphocytes; mouse bone marrow, liver, and kidney cells; fish gill cells and erythrocytes; caiman erythrocytes; tadpoles; sea urchin embryos; fruit flies; root-tip cells of onions; and in Salmonella bacteria. Other studies have shown that it causes oxidative stress, cell-cycle dysfunction, and disruption to RNA transcription, all of which can contribute to carcinogenicity. Laboratory studies have shown that very low levels of glyphosate, Roundup, POEA, and the metabolite AMPA all kill human umbilical, embryonic and placental cells. Roundup can reduce sperm numbers, increase abnormal sperm, retard skeletal development, and cause deformities in amphibian embryos. Exposure to glyphosate-based herbicides, even at very low doses may result in reproductive and hormonal problems, miscarriages, low birth weights, birth defects, and various cancers—especially haematological cancers such as non-Hodgkin’s lymphoma, and hormonal cancers such as breast cancer. Several epidemiological studies have linked exposure to glyphosate with non-Hodgkin’s lymphoma, hairy cell leukaemia, multiple myeloma, DNA damage; and one study with spontaneous abortions and pre-term deliveries. Neurological Glyphosate is assumed by regulators to have no neurological effects—the US EPA did not require neurotoxicity studies to be carried out for the registration of Roundup. However there is emerging evidence that glyphosate can affect the nervous system, and in particular areas of the brain associated with Parkinson’s disease. In one case study glyphosate exposure was linked to ‘symmetrical parkinsonian syndrome’. An epidemiological study of children identified a link with Attention-Deficit/Hyperactivity Disorder (ADHD). Other effects Glyphosate damages liver cells and interferes with a number of enzymes important in metabolism. Page 2-3 (Summary) The environmental effects of glyphosate of greatest concern are those that occur at a subtle level, and can result in significant disruption of aquatic and terrestrial eco-systems, including the agro-ecosystem. Page 16 Most recently a leading Argentinean scientist, Professor Carrasco of the University of Buenos Aires Medical School, demonstrated significant consistent and systematic malformations in amphibian embryos resulting from very low dose exposure to glyphosate, and warned that comparable effects can happen in humans. In the first part of the study amphibian embryos were immersed in a solution of the herbicide 1,500 times weaker than that used in agriculture: the embryos suffered head deformities. In the second part, the embryos were injected with glyphosate, also at 1,500 times dilution: the impact was even more severe, demonstrating that it is the active ingredient, not the adjuvants that are the problem. Effects included reduced head size, genetic alterations in the central nervous system, increased death of cells that help form the skull, deformed cartilage, eye defects, and undeveloped kidneys. Carrasco also stated that the glyphosate was not breaking down in the cells, but was accumulating. The findings lend weight to claims that abnormally high levels of cancer, birth defects, neonatal mortality, lupus, kidney disease, and skin and respiratory problems in populations near Argentina’s soybean fields may be linked to the aerial spraying of Roundup (Valente 2009; Trigona 2009; Ho 2009). |


