Pesticide profiles : Toxicity, environmental impact and fate - Chapter 4 pot

© 2000 CRC Press LLC chapter four Thio- and dithiocarbamates 4.1. Class overview and general description Background Thio- and dithiocarbamates are each a special subclass of carbamates. As the class names imply, thiocarbamates have one sulfur atom substituted for an oxygen atom; dithiocarbamates, have two oxygen atoms replaced by sulfur. The general structures of the thiocarbamates and dithiocarbamates are illustrated in Figure 4.1; Table 4.1 lists the various thiocarbamate and dithiocarbamate compounds. As is true with the carbamates, the R groups may refer to alkyl, aryl, alkoxy, amide, or metallic substituents (1). The ethylene(bis)dithiocarbamates (EBDCs) commonly contain a metal in a complex or in a polymeric form (1). In the past, the EBDCs were the focus of considerable media and public attention because of concern about the long-term effects of exposure to the EBDCs and their breakdown product, ethylene thiourea (ETU) (2). These issues are discussed in greater detail in the section regarding the toxicological effects. Thiocarbamate and dithiocarbamate use The thio- and dithiocarbamates are widely used, mainly as fungicides on crops in the field or to protect against fungal diseases or rot during harvesting, transport, and storage. Some of them, such as EPTC and molinate, may be used for other purposes, such as the control of non-crop plants. They may be used in several forms, including granular formulations and emulsifiable concentrates. Most, if not all, of the thiocar- bamates and dithiocarbamates are registered as General Use Pesticides (GUPs) (3,4). Mode of action and toxicology Thiocarbamates will have similar action to the carbamates, whose primary effects on target and non-target species are through the inhibition of a enzyme known as A B Figure 4.1 Generic structures for thiocarbamates (A) and dithiocarbamates (B). © 2000 CRC Press LLC acetylcholinesterase (AChE) (1). Acetylcholine (ACh) is a substance that transmits a nerve impulse from a nerve cell to a specific receptor such as another nerve cell or a muscle cell (5). ACh, in essence, acts much like a chemical switch. When it is released to a nerve cell at the synapse, it turns the receiving nerve cell “on” and results in transmission of a nerve impulse. The transmission of nervous energy continues until the ACh is broken down (by cleavage of the ester bond) into choline and acetic acid by AChE. Thiocarbamate inhibition of ACh is a reversible process. Estimates of the recovery time in humans range from immediate up to 4 days, depending on the dose, the specific pesticide, and the method of exposure (i.e., inhalation or ingestion) (6). The effects on nerve cells may result in incoordination, muscular weakness, disruption of concentration or reasoning abilities, disruption in regulation of heartbeat and breathing, and in extreme cases, convulsions (6). The dithiocarbamates may also result in nervous system effects, but not through the same mechanism as the thiocarbamates (1). The dithiocarbamates do not readily interact with AChE, but instead affect the nervous system through their main metab- olite, carbon disulfide (1). This compound affects the ability of the nerve cell to effectively conduct nervous impulses by altering the permeability of the nerve cell membrane and myelin sheath (1). A major toxicological concern with respect to the EBDCs is the metabolite, ethylenethiourea (ETU), which has been shown to cause thyroid and carcinogenic effects in test animals. The precise mechanism by which this may occur is not well understood (1,2). Table 4.1.a Thiocarbamates Butylate* Molinate* Cartap Orbencarb Cycloate Pebulate Diallate Prosulfocarb Dimepiperate Pyributicarb EPTC* Thiobencarb Esprocarb Thiocarbazil Fenothiocarb Triallate* Methasulfocarb Vernolate Note: * indicates that a profile for this compound is included in this chapter. Table 4.1.b Dithiocarbamates Methyldithiocarbamates Metham-sodium Dimethyldithiocarbamates Dimethyldithiocarb (DDC) Thiram* Ferbam Ziram* Diethyldithiocarbamates Sulfallate Ethylene(bis)dithiocarbamates Anobam Maneb* Cufraneb Metiram* Mancozeb* Zineb* Note: * indicates that a profile for this compound is included in this chapter. © 2000 CRC Press LLC Acute toxicity Most members of the thiocarbamate and dithiocarbamate classes are slightly to practically nontoxic via ingestion, dermal and inhalation routes. Most cause skin and/or eye irritation and may cause skin sensitization (allergic contact reaction). Via the oral route, the reported acute LD 50 values range from 300 to 400 mg/kg to greater than 5000 mg/kg in rats and other test animals, indicating they are practically nontoxic (1,4,6,7). Slight toxicity is also observed via the dermal route (2,3). The reported acute dermal LD 50 values for the thio- and dithiocarbamate pesticides in rats are almost all greater than 2000 mg/kg (3,6,7). For many, mild to moderate skin sensitization and/or skin and eye irritation has been observed in test animals. Although precise acute inhalation LC 50 values were not available for all of the thio- and dithiocarbamates, most are of moderate to slight toxicity by this route (1,4,6,7). Effects due to exposure to some of the thio- and/or dithiocarbamates (notably EPTC) may include those similar to exposure to carbamates, i.e., cholinesterase inhibition (1,4,6,7). These include blurred vision, fatigue, headache, dizziness, abdominal cramps, and diarrhea. Severe inhibition of cholinesterase may cause excessive sweating, tearing, slowed heartbeat, giddiness, slurred speech, confusion, excessive fluid in the lungs, convulsions, and coma. Dithiocarbamates are partially metabolized to carbon disulfide, a neurotoxin capable of interfering with nerve transmission (6–8). Chronic toxicity Thiocarbamates Some thiocarbamates have been associated with cholinesterase inhibition, degen- eration of nervous tissue (of the spinal cord, muscles, and heart), and increased liver and thyroid weights in long-term animal studies. The doses required to produce these effects ranged from 2 mg/kg/day (in rats over two generations) to greater than 15 mg/kg/day (in dogs over 2 years) (1,6,8). High variability in some toxic responses was seen across species. Repeated application of some thiocarbamates caused skin irritation (6,8). Dithiocarbamates Symptoms of chronic exposure to dithiocarbamates may include neurological and/or behavioral effects (e.g., drowsiness, incoordination, weakness, and paralysis) in addition to those due to acute exposure. Doses on the order of 40 to 50 mg/kg/day were required to produce these effects in rats; doses of about 5 mg/kg/day (e.g., thiram and ziram) reportedly caused no observed effects in dogs over 1 year. Repeated or prolonged exposure to dithiocarbamates can also cause skin sensitiza- tion (1,6). Ethylene(bis)dithiocarbamates (EBDCs) As mentioned above, a major toxicological concern in cases of chronic exposure to the EBDCs (e.g., mancozeb, maneb, metiram, and ziram) is ethylenethiourea (ETU), which may be produced during metabolism, and also may be introduced as a contaminant during manufacture (1). ETU may also be generated in small amounts when EBDC residues are present on produce for long periods, or during cooking © 2000 CRC Press LLC (1). In test animals, ETU has caused thyroid enlargement (also known as goiter) and impaired thyroid function, birth defects, and cancers (1). Indeed, it may be that ETU (formed during metabolism) is responsible for the thyroid effects seen in test animals after long-term exposure to EBDCs (1). The EBDC dose levels required to produce observable effects in long-term (2- year) animal dietary studies range from about 2 to 5 mg/kg/day in dogs and rats (for mancozeb) (1,9) and greater than 12.5 mg/kg/day in rats (for maneb) (1,10). Effects observed were thyroid enlargement and impairment. At higher daily doses, some EBDCs caused gastrointestinal and nervous system disturbances (muscular weakness and tremor) in these animals. For metiram, no observed adverse effects were seen at doses of up to 45 mg/kg/day following a course of 90 days of exposure in dogs (1,11). Zineb failed to produce effects on survival, growth, and blood chem- istry in dogs fed doses of 250 mg/kg/day over a 1-year period (1). Field studies of some EBDCs have shown that they may cause skin or eye irritation and/or contact dermatitis (1). Reproductive effects For the majority of the thio- and dithiocarbamates, no reproductive effects were observed in test animals receiving doses of about 20 to 30 mg/kg/day during pregnancy (1,6,8). At higher doses (e.g., 50 mg/kg/day for mancozeb and 100 mg/kg/day for EPTC), effects such as decreased offspring weight gain and lower fertility rates were seen. The EBDCs have produced reproductive effects in some animal systems, but only at extremely high levels (1,2,9–11). It does not seem likely that these classes of pesticides will produce reproductive effects in humans under normal circumstances. Teratogenic effects With the majority of members of the thio- and dithiocarbamate class, teratogenic effects were observed in various single- and multi-generational rat and rabbit studies at dietary doses ranging from 50 to as high as 1000 mg/kg/day (1,6,12). With respect to the EBDCs, developmental toxicity was observed at lower doses such as 5 to 10 mg/kg/day (2,9–11). Teratogenic effects were also observed with some EBDCs (e.g., mancozeb) following single massive oral doses during pregnancy. The EDBCs have been shown to be teratogenic in rats and hamsters, but not in mice (1,12). Teratogenic effects in humans are unlikely at normal levels of exposure. Mutagenic effects Most of the thio- and dithiocarbamates appear to be nonmutagenic or only very weakly mutagenic as indicated by a variety of mutagenicity assays (1,4,6). A notable exception to this general finding is ziram (an EBDC), which has been observed to increase chromosomal aberrations in tissues from occupationally exposed workers and test animals (1,6,8). Carcinogenic effects No carcinogenic activity is reported for the majority of the thio- and dithiocar- bamates studied. There is, however, evidence for the carcinogenicity of many of the EBDCs at high doses. This may be due to ETU, a major metabolite of EBDCs, which has been demonstrated to be carcinogenic in test animals (1). © 2000 CRC Press LLC Organ toxicity The primary target organs for the thio- and dithiocarbamates include the nervous system, thyroid, and liver. Kidney injury was observed as a result of exposure to some pesticides in these classes (1,6,8). Fate in humans and animals In general, thiocarbamates and dithiocarbamates are rapidly absorbed into the bloodstream from the gastrointestinal tract, and to a lesser extent into the lung. Thiocarbamates are readily broken down and excreted by treated animals (1,6). Some dithiocarbamates may be less well absorbed (e.g., ziram) and others may accumulate to some degree at sites where toxicity may occur (e.g., the thyroid, liver, nervous system, etc.) (6). In the body, carbon disulfide results from metabolism of the thio- and dithiocarbamates, and may contribute to their toxic effects (6). Members of the EBDC chemical family are generally well absorbed through all routes. Breakdown products in animal systems include carbon disulfide and ETU (1,2). Ecological effects Effects on birds Thio- and dithiocarbamates are generally of slight toxicity to birds. In most cases, the reported acute oral LD 50 values are greater than 5000 mg/kg. The 8-day dietary LC 50 values for the thio- and dithiocarbamates in birds, greater than 2000 ppm, indicate they are practically nontoxic to avian species (3,7,12–15). Effects on aquatic organisms The toxicity of the thio- and dithiocarbamates to aquatic organisms is variable, but the majority are moderately to highly toxic, with reported 96-hour LC 50 values of about 1 to 10 mg/L. Others may be only slightly toxic (e.g., EPTC and metiram), with reported 96-hour LC 50 values of about 20 mg/L (3,7,16–18). Reported biocon- centration factors and residence times in various types of fish generally indicate that members of these chemical families will not significantly accumulate in these organ- isms (16–19). Effects on other organisms (non-target species) Most thio- and dithiocarbamates are nontoxic to bees, both through contact and ingestion (3,4). Environmental fate Fate in soil and groundwater Most of the thio- and dithiocarbamates are of low to moderate persistence, with reported field half-lives of a few days to several weeks (19–21). They are also poorly bound to soils, reasonably soluble in water, and therefore somewhat mobile. As a result, they may present a risk to groundwater, especially in highly porous soils with very little soil organic matter. Most are subject to microbial breakdown and volatilization. Members of the EBDC group are of low persistence, with reported field half- lives of 1 to several days (19–21). They all rapidly and spontaneously degrade to © 2000 CRC Press LLC ETU in the presence of water and oxygen (19–21). Because the EDBCs are strongly bound to soils, practically insoluble in water, and show a very short field residence time under normal circumstances, they generally do not present a risk to ground- water (19–21). ETU, though, is less strongly bound, more water soluble, and may persist for several weeks to a few months (19–21). ETU therefore does have the potential to be mobile and contaminate groundwater supplies. However, ETU, the primary break- down product of the EDBCs in soils, has been detected (at 16 ppb) in only 1 out of 1295 drinking water wells tested (22). Fate in water Many of the thio- and dithiocarbamates undergo hydrolysis, and breakdown by microbial action may be slow. The low water solubility of the compounds means that they will either be broken down or sorbed to sediment, where they may persist for several weeks or months. Breakdown of the EBDCs to ETU is very rapid, mainly by hydrolysis, and to a lesser degree by photodegradation (19–21). None of these compounds are expected to be persistent in the surface water environment. Fate in vegetation Most thio- and dithiocarbamates are readily taken up and translocated within plants, and rapidly processed into carbon dioxide and fatty acids (6,7). Most are not persistent within plants and do not leave significant residues. In most plant systems, the EBDCs are not readily taken up and translocated (4). If they are, they are degraded to ETU and then rapidly metabolized further to less-toxic breakdown products. 4.2Individual Profiles 4.2.1 Butylate Trade or other names Trade names include Anelirox, Anelda Plus, Aneldazin, Butilate, Carbamic Acid, Ethyl N, Genate, Genate Plus, N-Diisobutylthiocarbamate, R1910, Stauffer R-1, Sutan, and Sutan 6E. Regulatory status Butylate is classified by the U.S. Environmental Protection Agency as a General Use Pesticide (GUP), with applications limited to corn fields. It is categorized Figure 4.2 Butylate. © 2000 CRC Press LLC toxicity class III — slightly toxic. Products containing butylate bear the Signal Word CAUTION. Introduction Butylate is a herbicide and a member of the thiocarbamate class of chemicals. It is registered only for use in corn to control grassy weeds such as nutgrass and millet grass, as well as some broadleaf weeds. It is applied to soil immediately before corn is planted, often in combination with atrazine and/or cyanazine. Butylate acts selec- tively on seeds of weeds that are in the germination stage of development. It is absorbed from the soil by shoots of grass seedlings before they emerge, causing shoot growth to be slowed and leaves to become twisted. Toxicological effects Acute toxicity The major routes of exposure to butylate are through the skin and by inhalation. Butylate is a thiocarbamate, a class of chemicals known for their tendency to irritate the skin and the mucous membranes of the respiratory tract. It may cause symptoms of scratchy throat, sneezing, and coughing when large amounts of dusts or spray are inhaled (4,7). Slight eye irritation can be caused by butylate, potentially leading to permanent eye damage (7,22). Skin irritation was observed in rabbits topically exposed to 2000 mg technical butylate (85.71% pure) for 24 hours. The acute dermal LD 50 for butylate is greater than 4640 mg/kg in rabbits (7). Butylate causes irritation to the eyes of rabbits (23). The oral LD 50 for butylate ranges from 1659 mg/kg in male guinea pigs to 5431 mg/kg in female rats. Butylate’s inhalation LC 50 (2-hour) is 19 mg/L (3,23). Chronic toxicity Application of 21 doses of 20 and 40 mg/kg/day to the skin of rabbits caused no effects other than local skin irritation (23). Liver changes were produced by doses of 180 mg/kg/day in a 56-week rat study with butylate. Blood clotting was affected by 10 mg/kg/day in the same experiment (24). Several studies have shown that long-term exposure to high doses of butylate causes increases in liver weights in test animals (23). When butylate was fed to rats at doses of 50, 100, 200, or 400 mg/kg/day for 2 years, body weights were decreased and liver-to-body weight ratios increased at all but the lowest dose tested. In rats fed 20, 80, or 120 mg/kg/day for 2 years, no effects were observed at the 20 mg/kg dose, but kidney and liver lesions formed at the two higher doses. Butylate fed to rats at 10, 30, and 90 mg/kg/day for 56 weeks affected blood clotting at all doses. At the two higher doses, body weight and testes:body weight ratios decreased, liver:body weight ratios increased, and lesions formed on the testes. In a study of dogs fed 5, 25, or 100 mg/kg/day for 12 months, decreased body weights, increased liver weights, and increased incidence of liver lesions were observed at the highest dose (23). Reproductive effects No reproductive effects were observed in test animals receiving doses of up to 24 mg/kg/day of butylate (24). Long-term consumption of water containing butylate © 2000 CRC Press LLC at very high doses caused damage to testes in rats (4). Butylate is unlikely to cause reproductive effects in humans at expected exposure levels. Teratogenic effects No teratogenic effects were observed in offspring of mice ingesting 4 to 24 mg/kg/day of Sutan during days 6 through 18 of pregnancy. No teratogenic effects were observed in the offspring of rats given up to 1000 mg/kg/day on days 6 through 20 of pregnancy or in the offspring of rabbits given doses of up to 500 mg/kg/day on days 6 through 18 of gestation (23,24). However, in a study of two generations of offspring from rats fed for 63 days before mating, decreased brain weights were observed in the first generation of offspring at the 50-mg/kg/day dose level. At 200 mg/kg/day, adverse effects on the eyes and kidneys of the first generation were observed. This evidence suggests that butylate is unlikely to cause teratogenic effects in humans under normal cir- cumstances. Mutagenic effects Mutations were seen in mice given very high oral doses of 1000 mg/kg/day of the herbicide (25). It was not mutagenic in the Ames test performed on Salmonella bacteria (4,24). Butylate thus is nonmutagenic or very weakly mutagenic. Carcinogenic effects There was no tumor formation related to doses of up to 320 mg/kg/day herbi- cide in a 24-month study of rats. Thus, butylate does not appear to be carcinogenic (24). Organ toxicity Animal studies have shown the liver and male reproductive system as the target organs. Fate in humans and animals Butylate is rapidly metabolized and excreted in animals (24). Within 48 hours after administration of butylate to rats by gavage, 27.3 to 31.5% of the material is eliminated through the urine, 60.9 to 64% is expired as carbon dioxide, and 3.3 to 4.7% is excreted in the feces. Only 2.2 to 2.4% of the compound is retained in the body, with most of this located in the blood, kidneys, and liver (23). Ecological effects Effects on birds Given its low toxicity, butylate is considered a minimal hazard to birds (24). Technical butylate has an acute oral LD 50 greater than 4640 mg/kg in mallard ducks. Its 8-day dietary LC 50 in bobwhite quail is estimated at 40,000 ppm (22). Effects on aquatic organisms Butylate is moderately toxic to fish (3). It has a low to moderate potential for bioaccumulation in fish (23). The LC 50 for a 96-hour exposure to technical Sutan ranges from 4.2 mg/L in rainbow trout to 6.9 mg/L in bluegill sunfish (24). © 2000 CRC Press LLC Effects on other organisms (non-target species) Butylate is not harmful to bees if it is used appropriately (3). It appears to pose few, if any, acute toxicological hazards to non-target wildlife (24). Environmental fate Breakdown in soil and groundwater Butylate has a low to moderate persistence in soil. The soil half-life is 3 to 10 weeks in moist soils under aerobic conditions. Under anaerobic conditions, buty- late has a half-life of 13 weeks (23). In loamy soil, at 70 to 80 ° F, its half-life is 3 weeks (7). Soil half-lives of 12 days, and 1 1 / 2 to 3 weeks have also been reported (7,20). Butylate is one of the pesticide compounds that the EPA considers to have the greatest potential for leaching into groundwater although it is only slightly soluble in water (23). Butylate does not strongly adsorb to soil particles and is slightly to highly mobile in soils, depending on the soil type (20,23). Leaching is more likely to occur in sandy, dry soils, and is less likely to occur in soil with higher amounts of organic matter and clay. An EPA study found butylate in 2 out of 152 groundwater samples analyzed (23). Butylate degrades to sulfoxide in soil (8). Butylate has a residual activity in soil of approximately 4 months, when it is applied at 5 to 6 mg/hectare (3). When applied to dry soil surfaces, very little butylate is lost through vaporization. However, it can be lost by vaporization when applied to the surface of wet soils without being sufficiently incorporated (7). Breakdown in water Very low concentrations of butylate (maximum of 0.0047 mg/L) were found in 91 of 836 surface water samples analyzed (23). Breakdown in vegetation Butylate is readily adsorbed by plant leaves, but does not usually come in contact with foliage. It is rapidly taken up by the roots of corn plants and moved upward throughout the entire plant (7). Butylate is rapidly broken down in corn roots and leaves, to carbon dioxide, fatty acids, and certain natural plant constituents (7,22). It is not thought to persist in plants since it disappeared from the stems and leaves of corn plants 7 to 14 days after treatment. The injury that it causes is not limited to that part of the plant to which it is applied (26). Physical properties Technical butylate is a clear amber to yellow liquid with an aromatic odor (3). Chemical name: S-ethyl-di-isobutylthiocarbamate (3) CAS #: 2008-41-5 Molecular weight: 217.38 (3) Water solubility: 45 mg/L in water @ 22 ° C (3) © 2000 CRC Press LLC Solubility in other solvents: kerosene v.s.; xylene v.s.; acetone v.s.; ethyl alcohol v.s. (3) Vapor pressure: 170 mPa @ 25 ° C (3) Partition coefficient (octanol/water): 14,000 (3) Adsorption coefficient: 400 (20) Exposure guidelines ADI: Not available HA: 0.35 mg/L (4) RfD: 0.05 mg/kg/day (27) PEL: Not available Basic manufacturer Zeneca Ag Products 1800 Concord Pike Wilmington, DE 19897 Telephone:800-759-4500 Emergency:800-759-2500 4.2.2 EPTC Trade or other names Trade names include Alirox, Eptam, Eradicane, Eradicane Extra, Genep, Genep Plus, and Shortstop. Regulatory status EPTC is a slightly toxic compound in EPA toxicity class III. It is a General Use Pesticide (GUP); labels for products containing EPTC must bear the Signal Word CAUTION. Introduction EPTC is a selective thiocarbamate herbicide used for control of annual grassy weeds, perennial weeds, and some broadleaf weeds in beans, forage legumes, pota- toes, corn, and sweet potatoes. It is usually applied pre-emergence (i.e., before weed seeds germinate) and is usually incorporated into the soil immediately after appli- cation either mechanically or by overhead irrigation. EPTC is available as emulsifi- able concentrates and granular formulations. Figure 4.3 EPTC. [...]... Melting point: 29–30°C (3) Vapor pressure: 16 mPa @ 25°C (3) Partition coefficient (octanol/water) not available Adsorption coefficient: 240 0 (20) Exposure guidelines ADI: Not available HA: Not available RfD: 0.013 mg/kg/day (27) PEL: Not available Basic manufacturer Monsanto Company 800 N Lindbergh Blvd St Louis, MO 63167 Telephone: 31 4- 6 9 4- 6 640 Emergency: 31 4- 6 9 4- 4 000 4. 2.9 Zineb Figure 4. 10 Zineb Trade... Melting point: Not available Vapor pressure: 47 00 mPa @ 25°C (3) Partition coefficient (octanol/water ): 1600 (3) Adsorption coefficient: 200 (20) Exposure guidelines ADI: Not available HA: Not available RfD: Not available PEL: Not available Basic manufacturer Zeneca Ag Products 1800 Concord Pike Wilmington, DE 19897 Telephone: 80 0-7 5 9 -4 500 Emergency: 80 0-7 5 9-2 500 4. 2.3 Mancozeb Figure 4. 4 Mancozeb Trade... Vapor pressure: 746 mPa @ 25°C (3) Melting point: Not available Partition coefficient (octanol/water ): 760 (3) Adsorption coefficient: 190 (20) Exposure guidelines ADI: Not available HA: Not available RfD: 0.002 mg/kg/day (27) PEL: Not available Basic manufacturer Zeneca Ag Products 1800 Concord Pike Wilmington, DE 19897 Telephone: 80 0-7 5 9 -4 500 Emergency: 80 0-7 5 9-2 500 4. 2.7 Thiram Figure 4. 8 Thiram Trade... acids and organic acids in nonsusceptible plants Physical properties Molinate is a noncorrosive, clear liquid with an aromatic or spicy odor (3) Chemical name: S-ethyl hexhydro-1 H-azepine-1-carbothioate (3) CAS #: 221 2-6 7-1 Molecular weight: 187.30 (3) © 2000 CRC Press LLC Solubility in water: 880 mg/L (3) Solubility in other solvents: v.s in acetone, xylene, ethanol, kerosene, and 4methylpentan-2-one... Triallate is absorbed and metabolized by plants (39) Physical properties Triallate is an amber, oily liquid (3) Chemical name: S-(2,3,3-trichloro-2-propenyl)bis(1-methylethyl) carbamothioate (3) CAS #: 230 3-1 7-5 © 2000 CRC Press LLC Molecular weight: 3 04. 66 (3) Water solubility: 4 mg/L @ 25°C (3) Solubility in other solvents: s in acetone, ether, ethyl alcohol, heptane, benzene, ethyl acetate, and most organic... organisms Maneb is highly toxic to fish and aquatic species The 96-hour LC50 for maneb is 1 mg/L in bluegill sunfish ( 34) The reported 48 -hour LC50 is 1.9 mg/L in rainbow © 2000 CRC Press LLC trout, and 1.8 mg/L in carp ( 34) The 72-hour LC50 is more than 40 mg/L in crayfish, and the 48 -hour LC50 is 40 mg/L in tadpoles ( 34) Effects on other organisms (non-target species) Maneb-treated crop foliage may be toxic... 80038 Wilmington, DE 1988 0-0 038 Telephone: 80 0 -4 4 1-7 515 Emergency: 80 0 -4 4 1-3 637 4. 2 .4 Maneb Trade or other names Trade names include Farmaneb, Manesan, Manex, Manzate, Nereb, and Newspor © 2000 CRC Press LLC Figure 4. 5 Maneb Regulatory status Maneb is a practically nontoxic ethylene(bis)dithiocarbamate in EPA toxicity class IV It is registered as a General Use Pesticide (GUP) Labels for products containing... (estimated) (20) Exposure guidelines ADI: 0.03 (33) HA: Not available RfD: Not available PEL: Not available Basic manufacturer BASF Corp Agricultural Products Group P.O Box 13528 Research Triangle Park, NC 2770 9-3 528 Telephone: 80 0-6 6 9-2 273 Emergency: 80 0-8 3 2 -4 357 4. 2.6 Molinate Figure 4. 7 Molinate Trade or other names Trade names include Hydram, Molinate, Ordram, and Yalan Regulatory status Molinate... name: zinc ammoniate ethylenebis(dithiocarbamate)-poly(ethylene thiuram disulfide) (3) CAS #: 900 6 -4 2-2 Molecular weight: 1088.7 (3) Water solubility: . 80038 Wilmington, DE 1988 0-0 038 Telephone:80 0 -4 4 1-7 515 Emergency:80 0 -4 4 1-3 637 4. 2 .4 Maneb Trade or other names Trade names include Farmaneb, Manesan, Manex, Manzate, Nereb, and Newspor. © 2000 CRC. name: S-ethyl-di-isobutylthiocarbamate (3) CAS #: 200 8 -4 1-5 Molecular weight: 217.38 (3) Water solubility: 45 mg/L in water @ 22 ° C (3) © 2000 CRC Press LLC Solubility in other solvents:. guidelines ADI: Not available HA: Not available RfD: Not available PEL: Not available Basic manufacturer Zeneca Ag Products 1800 Concord Pike Wilmington, DE 19897 Telephone:80 0-7 5 9 -4 500 Emergency:80 0-7 5 9-2 500 4. 2.3