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Offline electronicsunset

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arsenic
« on: 23/09/2007 17:34:21 »
What is arsenic still used for in the UK? In particular, is it still in rat poison and weedkiller or has it been banned?

cheers


 

another_someone

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arsenic
« Reply #1 on: 23/09/2007 17:46:05 »
http://en.wikipedia.org/wiki/Arsenic#Applications
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Lead hydrogen arsenate has been used, well into the 20th century, as an insecticide on fruit trees (sometimes resulting in brain damage to those working the sprayers), and Scheele's Green (a copper arsenate) has even been recorded in the 19th century as a coloring agent in sweets. In the last half century, monosodium methyl arsenate (MSMA), a less toxic organic form of arsenic, has replaced lead arsenate's role in agriculture.

The application of most concern to the general public is probably that of wood which has been treated with chromated copper arsenate ("CCA", or "Tanalith", and the vast majority of older "pressure treated" wood). CCA timber is still in widespread use in many countries, and was heavily used during the latter half of the 20th century as a structural, and outdoor building material, where there was a risk of rot, or insect infestation in untreated timber. Although widespread bans followed the publication of studies which showed low-level leaching from in-situ timbers (such as children's playground equipment) into surrounding soil, the most serious[citation needed] risk is presented by the burning of CCA timber. Recent years have seen fatal animal poisonings, and serious human poisonings resulting from the ingestion - directly or indirectly - of wood ash from CCA timber (the lethal human dose is approximately 20 grams of ash). Scrap CCA construction timber continues to be widely burnt through ignorance, in both commercial and domestic fires. Protocols for safe disposal of CCA timber are still in place only patchily; there is concern in some quarters about the widespread landfill disposal of such timber.

During the 18th, 19th, and 20th centuries, a number of arsenic compounds have been used as medicines, including arsphenamine (by Paul Ehrlich) and arsenic trioxide (by Thomas Fowler). Arsphenamine as well as Neosalvarsan was indicated for syphilis and trypanosomiasis, but has been superseded by modern antibiotics. Arsenic trioxide has been used in a variety of ways over the past 200 years, but most commonly in the treatment of cancer. The Food and Drug Administration in 2000 approved this compound for the treatment of patients with acute promyelocytic leukemia that is resistant to ATRA.[1] It was also used as Fowler's solution in psoriasis.[2]

Copper acetoarsenite was used as a green pigment known under many different names, including 'Paris Green' and 'Emerald Green'. It caused numerous arsenic poisonings.

Other uses;
  • Various agricultural insecticides, termination and poisons.
  • Gallium arsenide is an important semiconductor material, used in integrated circuits. Circuits made using the compound are much faster (but also much more expensive) than those made in silicon. Unlike silicon it is direct bandgap, and so can be used in laser diodes and LEDs to directly convert electricity into light.
  • Also used in bronzing and pyrotechny.

There is no mention of whether it is still available as a rat poison, but I suspect it is not available over the counter as such, but very possibly available to professional pest controllers (I don't know the answer to this, but I might know a man who might - if you don't get a better answer, I could ask him).
« Last Edit: 23/09/2007 17:48:07 by another_someone »
 

another_someone

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arsenic
« Reply #2 on: 23/09/2007 18:00:18 »
http://www.pan-uk.org/pestnews/Issue/pn54/pn54p3.htm
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Table 1. Prohibited pesticides
M&S says the following 79 pesticides are a priority for action and will prohibit their use on produce it purchases throughout the world in a phased approach starting 1 January 2002:

UK usage 2-aminobutane, Atrazine, Bromoxynil, Carbaryl, Carbofuran, Chlorfenvinphos, Dichlorvos, Dimethoate, Disulfoton, Endosulfan, Etrimfos, Fenitrothion, Fentin acetate, Lindane, Malathion, Maneb, Methomyl, Methyl bromide, Permethrin, Propoxur, Quintozene, Simazine, Sulphuric acid, Tecnazene, Tridemorph, Vinclozolin.

Non UK usage 2,4,5-T, Acetochlor, Alachlor, Aldrin, Antu, Azinphos-methyl, Azobenzene, Binapacryl, Cadmium compounds, Calcium arsenate, Camphechlor, Captafol, Chlordane, Chlordecone, Chlordimeform, Chlorobenzilate, Cyhexatin, DDT, Demeton-S-methyl, Diazinon, Dieldrin, Dinoseb, Dinoterb, DNOC, EDB, EDC, Endrin, Ethiofencarb, Ethylene oxide, Fluoracetamide, HCB, HCH, Heptachlor, Heptenophos, Mephosfolan, Mercury compounds, Methamidophos, Methyl parathion, Monocrotophos, Nitrofen, Parathion, Pentachlorophenol, Phosalone, Phosphamidon, Potassium arsenite, Pyrazophos, Quinalphos, Selenium compounds, Sodium arsenite, 1,1,2,2-tetrachloroethane, Thiometon, Toxaphene, Trichlorfon.

You will note that as at 2002, Sodium Arsenite, Potassium Arsenite, and Calcium Arsenate, are on the list of pesticides used outside of the UK, but not within the UK.
 

another_someone

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arsenic
« Reply #3 on: 23/09/2007 18:07:35 »
Th following is a table pesticides, and their status within the UK:

http://pesticideinfo.org/Detail_Country.jsp?Country=United%20Kingdom

It quotes arsenic as not banned, but severely restricted.
 

Offline iko

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arsenic
« Reply #4 on: 23/09/2007 18:12:05 »
Yes George,

arsenic seems to be severely restricted, but not banned, and still a matter of concern for public health:


Chromium on the hands of children after playing in playgrounds built from chromated copper arsenate (CCA)-treated wood.

Hamula C, Wang Z, Zhang H, Kwon E, Li XF, Gabos S, Le XC.Environmental Health Sciences, Department of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada.

Children's exposure to arsenic and chromium from playground equipment constructed with chromated copper arsenate (CCA)-treated wood is a potential concern because of children's hand-to-mouth activity. However, there exists no direct measure of Cr levels on the hands of children after playing in such playgrounds. In this study we measured both soluble and total Cr on the hands of 139 children playing in playgrounds, eight of which were constructed with CCA-treated wood and eight of which were not. Children's age and duration of play were recorded. The hands of each child were washed after play with 150 mL deionized water, which was collected in a bag and subsequently underwent analysis of Cr and 20 other elements, using inductively coupled plasma mass spectrometry. Total average Cr on the hands of 63 children who played in CCA playgrounds was 1,112 +/- 1,089 ng (median, 688; range 78-5,875). Total average Cr on the hands of 64 children who played in non-CCA playgrounds was 652 +/- 586 ng (median, 492; range 61-3,377). The difference between the two groups is statistically significant (p < 0.01). Cr levels were highly correlated to both Cu (r = 0.672) and As (r = 0.736) levels in CCA playgrounds (p < or = 0.01), but not non-CCA playgrounds (r = 0.252 and 0.486 for Cu and As, respectively). Principal-component analysis indicates that Cr, Cu, and As are more closely grouped together in CCA than in non-CCA playgrounds. These results suggest that the elevated levels of Cr and As on children's hands are due to direct contact with CCA wood.

Environ Health Perspect. 2006 Mar;114(3):460-5.



« Last Edit: 23/09/2007 18:14:46 by iko »
 

another_someone

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arsenic
« Reply #5 on: 23/09/2007 18:18:48 »
Yes George,

arsenic seems to be severely restricted, but not banned, and still a matter of concern for public health:

The reference you had referred to Canada, although in this case I believe the situation is the same in the UK.

From what I had managed to ascertain, CCA treated wood is now banned in the UK (and I suspect in Canada), but there is a lot of wood around that pre-dates the ban, and the problem is when this wood is burnt, the ash becomes a liability.
 

Offline electronicsunset

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arsenic
« Reply #6 on: 23/09/2007 19:34:43 »
So from what I've gleaned it's restricted in the UK as a herbicide, insecticide and rodenticide and banned in anti-foulant paints and wood preservative.There seems to be an EU directive that I can't quite fathom, so my next stop in my quest to find out then is Rentokill or their ilk.

I'm trying to compile most of the elements from items purchased at car-boot sales and second-hand stalls (and will be holding a car-boot sale presented as the periodic table at the end of the process), and I'm naturally having trouble with a few of them.

Thanks for the info.

Kyp
 

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arsenic
« Reply #6 on: 23/09/2007 19:34:43 »

 

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