|CAS Number: 116-06-3|
|Synonyms: Ambush, OMS 771, Temic, Temik, UC 21149 , Unioin Carbide 21149|
|Contaminant Type: Chemical|
Aldicarb is a systemic carbamate pesticide applied to the soil for control of insect, mite and nematode pests in plants . Its chemical name is 2-methyl-2-(methylthio) propionaldehyde O-methylcarbamoyl) oxime, with trade names of Temik or , UC21149 .
Since its introduction in 1970s, aldicarb is used widely on cotton, soybeans, peanuts and many other crops all over the world. The United States consumes approximately 70% of world production . Due to aldiarb’s contamination of groundwater, Union Carbide Corporation excluded or limited the use of aldicarb products in some states (certain area or the whole state) in the United States, including New York, Maine, Wisconsin, Connecticut, Delaware, Massachusetts, Maryland, Atlantic Region, New Jersey, Rhode Island, and Virginia .
On July 1, 1991, the USEPA established maximum contaminant levels (MCLs) and maximum contaminant level goals (MCLGs) for aldicarb and its degradation products (aldicarb sulfoxide and aldicarb sulfone) with an effective date of January 1, 1993. The MCLs are 0.003 mg/L, 0.004 mg/L and 0.002 mg/L for aldicarb, aldicarb sulfoxide and aldicarb sulfone, respectively. The MCLGs are 0.001 mg/L for each of these three chemicals. However, the effective date was postponed by EPA on May 27, 1992. The MCLs and MCLGs are presently stayed [1492, 1493].
Aldicarb has been found to potentially cause nausea, diarrhea and relatively minor neurological symptoms as results of acute exposure at levels above the MCL of 0.003 mg/L . Chronic exposure to aldicarb above the MCL can potentially cause neurological effects, for example, sweating, papillary constriction and leg weakness . Aldicarb is categorized as “not classifiable as to human carcinogenicity” .
Aldicarb may be released to the environment during its manufacturing and usage as a pesticide. Since aldicarb is applied in soil, its primary release is to soil. Aldicarb degrades quickly in most soils. Half-lives of aldicarb in soil have been reported to be in a general range 1 to 15 days, depending on soil type, temperature, moisture and pH [1490, 1491]. Aldicarb is susceptible to alkaline hydrolysis so it is expected to be unstable in high soil pH . On the other hand, its persistence in acidic soils with pH below 5.5 is expected to be longer . Leaching studies have indicated that aldicarb is mobile in coarse sandy soil; however, leaching is limited in clay loam and muck soils .
Aldicarb is very persistent in groundwater, especially in water with low pH . Its half-life for degradation to non-toxic products ranges from a few weeks to years . The primary mode of degradation is chemical hydrolysis in cold areas and chemical hydrolysis and microbial decay in warm areas .
Date of Literature Search: June 2009
Tomlin, C.D.S. (Ed.);
The Pesticide Manual - World Compendium;
The Pesticide Manual - World Compendium;
Available: Hazardous Substances Data Bank: Aldicarb. <http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB>. [cited June 1, 2009]
1490 FAO and WHO; 1979; Pesticide Residues in Food - 1979. Evaluations 1979. Joint FAO/WHO Meeting on Pesticide Residues. Geneva, 3-12 December 1979. ; Pesticide Residues in Food - 1979. Evaluations 1979. Joint FAO/WHO Meeting on Pesticide Residues. Geneva, 3-12 December 1979.; Aldicarb.
1491 USEPA; 1995; Technical Factsheet on: Aldicarb and Metabolites; Contaminant Specific Fact Sheets; EPA 811-F-95-003-T
1492 USEPA; 1992; 40 CFR, Parts 141, 142, 143 National Primary Drinking Regulations; Aldicarb, Aldicarb Sulfoxide, and Aldiarb Sulfone; Postponement of Certain Provisions of Final Rule; Rules and Regulations; EPA 811-Z-92-001. Office of Water 4601. Federal Register, Vol. 57, No. 102, pp. 22178. May 27, 1992.
1493 USEPA; 2009; When did EPA promulgate the regulations for aldicarb, aldicarb sulfoxide, and aldicarb sulfone, and when did they become effective?; http://safewater.custhelp.com/cgi-bin/safewater.cfg/php/enduser/std_adp.php?p_faqid=1423&p_created=1099202571; As posted on June 1, 2009. USEPA Office of Ground Water and Drinking Water, Washington, DC.
1494 USEPA; 2006; 2006 Edition of the Drinking Water Standards and Health Advisories; 2006 Edition of the Drinking Water Standards and Health Advisories; EPA 822-R-06-013. pp. 1. USEPA Office of Water, Washington, DC.
1495 USEPA; 1984; EPA Notice Initiating Review of Aldicarb Pesticides; EPA Notice Initiating Review of Aldicarb Pesticides; Federal Register, 49:28320. Available: Canadian Federal-Provincial-Territorial Committee on Drinking Water. Aldicarb. <http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/aldicarb-aldicarbe/index-eng.php> [cited June 1, 2009]
1496 Jones, R.L., Garner, W.Y. (Ed.); 1986; Field, Laboratory and Modeling Studies on the Degradation and Transport of Aldicarb Residues in Soil and Ground Water; Evaluation of Pesticides in Groundwater.; Chapter 11. pp. 197-218. American Chemical Society. Washington, DC.
1497 Coppedge, J.R., Bull, D.L. and Ridgway, R.L.; 1977; Movement and persistence of aldicarb in certain soils; Arch. Environ. Contam. Toxicol.; 5:2:129