|
Hertford, NC | Good point IowaDan, I remember hearing a lecture at a pesticide class where the person mentioned that once testing methods become accurate enough, any substance known to man could probably be found in most any glass of drinking water. The only thing that keeps that from being true right now is the ability of the test to detect ultra low levels of chemicals.
On the subject of the level of danger that we are exposed to through very low levels of glyphosate, The LD50 (measure of toxicity) of glyphosate is somewhere around 5600mg/kg where that of aspirin is 1.5mg/kg. Therefore aspirin is 3733 times more toxic than glyphosate.
I ripped this off from EXTOXNET
Toxicological Effects:
Acute toxicity: Glyphosate is practically nontoxic by ingestion, with a reported acute oral LD50 of 5600 mg/kg in the rat. The toxicities of the technical acid (glyphosate) and the formulated product (Roundup) are nearly the same [58,96]. The oral LD50 for the trimethylsulfonium salt is reported to be approximately 750 mg/kg in rats, which indicates moderate toxicity [58]. Formulations may show moderate toxicity as well (LD50 values between 1000 mg/kg and 5000 mg/kg) [58]. Oral LD50 values for glyphosate are greater than 10,000 mg/kg in mice, rabbits, and goats [8,96]. It is practically nontoxic by skin exposure, with reported dermal LD50 values of greater than 5000 mg/kg for the acid and isopropylamine salt. The trimethylsulfonium salt has a reported dermal LD50 of greater than 2000 mg/kg. It is reportedly not irritating to the skin of rabbits, and does not induce skin sensitization in guinea pigs [58]. It does cause eye irritation in rabbits [58]. Some formulations may cause much more extreme irritation of the skin or eyes [58]. In a number of human volunteers, patch tests produced no visible skin changes or sensitization [58]. The reported 4-hour rat inhalation LC50 values for the technical acid and salts were 5 to 12 mg/L [58], indicating moderate toxicity via this route. Some formulations may show high acute inhalation toxicity [58]. While it does contain a phosphatyl functional group, it is not structually similar to organophosphate pesticides which contain organophosphate esters, and it does not significantly inhibit cholinesterase activity [1,58].
Chronic toxicity: Studies of glyphosate lasting up to 2 years, have been conducted with rats, dogs, mice, and rabbits, and with few exceptions no effects were observed [96]. For example, in a chronic feeding study with rats, no toxic effects were observed in rats given doses as high as 400 mg/kg/day [58]. Also, no toxic effects were observed in a chronic feeding study with dogs fed up to 500 mg/kg/day, the highest dose tested [58,97].
Reproductive effects: Laboratory studies show that glyphosate produces reproductive changes in test animals very rarely and then only at very high doses (over 150 mg/kg/day) [58,96]. It is unlikely that the compound would produce reproductive effects in humans.
Teratogenic effects: In a teratology study with rabbits, no developmental toxicity was observed in the fetuses at the highest dose tested (350 mg/kg/day) [97]. Rats given doses up to 175 mg/kg/day on days 6 to 19 of pregnancy had offspring with no teratogenic effects, but other toxic effects were observed in both the mothers and the fetuses. No toxic effects to the fetuses occurred at 50 mg/kg/day [97]. Glyphosate does not appear to be teratogenic.
Mutagenic effects: Glyphosate mutagenicity and genotoxicity assays have been negative [58]. These included the Ames test, other bacterial assays, and the Chinese Hamster Ovary (CHO) cell culture, rat bone marrow cell culture, and mouse dominant lethal assays [58]. It appears that glyphosate is not mutagenic.
Carcinogenic effects: Rats given oral doses of up to 400 mg/kg/day did not show any signs of cancer, nor did dogs given oral doses of up to 500 mg/kg/day or mice fed glyphosate at doses of up to 4500 mg/kg/day [58]. It appears that glyphosate is not carcinogenic [97].
Organ toxicity: Some microscopic liver and kidney changes, but no observable differences in function or toxic effects, have been seen after lifetime administration of glyphosate to test animals [97].
Fate in humans and animals: Glyphosate is poorly absorbed from the digestive tract and is largely excreted unchanged by mammals. At 10 days after treatment, there were only minute amounts in the tissues of rats fed glyphosate for 3 weeks [98]. Cows, chickens, and pigs fed small amounts of glyphosate had undetectable levels (less than 0.05 ppm) in muscle tissue and fat. Levels in milk and eggs were also undetectable (less than 0.025 ppm). Glyphosate has no significant potential to accumulate in animal tissue [99].
| |
|
- U.S. researchers find Roundup chemical in water, air - MFT1970 : 9/3/2011 12:41
- Re: U.S. researchers find Roundup chemical in water, air - paul the original : 9/3/2011 12:53
- Re: U.S. researchers find Roundup chemical in water, air - Ed Winkle : 9/3/2011 12:57
- RE: U.S. researchers find Roundup chemical in water, air - skicker : 9/3/2011 13:34
- RE: U.S. researchers find Roundup chemical in water, air - martin : 9/3/2011 13:35
- Re: U.S. researchers find Roundup chemical in water, air - Gerald J. : 9/3/2011 14:21
- Re: U.S. researchers find Roundup chemical in water, air - Cole Sibley : 9/3/2011 15:05
- RE: U.S. researchers find Roundup chemical in water, air - hinfarm : 9/3/2011 15:17
- Re: U.S. researchers find Roundup chemical in water, air - Galaxie64 : 9/3/2011 16:06
- RE: Add this to ur collection - hyseed : 9/3/2011 16:13
- RE: U.S. researchers find Roundup chemical in water, air - cornstar : 9/4/2011 07:07
- Re: U.S. researchers find Roundup chemical in water, air - JimmyP : 9/6/2011 20:11
|
U.S. researchers find Roundup chemical in water, air
