Dichloro toxicity

Dibenzo[b,/][l,5]diazocine, tetrahydro-conformation, 7, 704 Dibenzo[b,/][l,4]diazocinediones synthesis, 7, 675 Dibenzodioxin, 2,7-dichloro-toxicity, 3, 992 Dibenzodioxin, hexachloro-toxicity, 3, 992 Dibenzodioxin, octachloro-toxicity, 3, 992... 

Perthane [72-56-0] l,l-dichloro-2,2-bis-(4-ethyiphenyi)ethane (30) (mp 60—61°C) is a rapidly biodegradable insecticide with very low mammalian toxicity, rat oral LD q 8170 mg/kg. It has been used as a household insecticide. 

Lin, S. H. and Chen, Y. V., Adsorption and desorption characteristics of 1,1-dichloro-1-fluoroethane by granular activated carbon and activated carbon fiber, J. Environ. Sci. Health, Part A Toxic / Hazard Subst. Environ. Eng., 1996,31(6), 1279 1292. 

PCBs and PCTs are particularly troublesome liquids because of their toxicity and persistence in the environment. They are defined as polychlorinated biphenyls, polychlorinated terphenyls, monomethyl-dibromo-diphenyl metliane, monomethyl-dichloro-diphenyl metliane or monomethyl-tetrachlorodiphenyl methane. With low electrical conductivity and heat resistance they found wide use as dielectric fluids and were formerly used as hydraulic fluids. PCBs have not been made in the UK since 1977 and whilst most new uses for the substance are banned in most countries, around two-thirds of the 1.5 million tonnes manufactured in Europe and the US prior to 1985 still remain in equipment such as transformers. PCTs have been used in the past in a restricted range of specialist industrial applications. 

CH3OCH2CI, /-PT2NEt, 0°, 1 h 25°, 8 h, 86% yield. This is the most commonly employed procedure for introducing the MOM group. The reagent chloromethylmethyl ether is reported to be carcinogenic, and dichloromethylmethyl ether, a by-product in its preparation, is considered even more toxic. A preparation that does not produce any of the dichloro ether has been reported." ... 

Tests of biological activity revealed that compound [480], whose complete structure was determined to be (15,25,4R,5R, 1 F)-2-bromo-1 -bromomethyl-1,4-dichloro-5-(2 -chloroethenyl)-5-methylcyclohexane by X-ray crystallographic analysis, is very toxic to Chlorella fusca under laboratory conditions. The other compounds... 

Burton, D.J. and D.J. Fisher. 1990. Acute toxicity of cadmium, copper, zinc, ammonia, 3,3 -dichlorobenzidine, 2,6-dichloro-4-nitroaniline, methylene chloride, and 2,4,6-trichlorophenol to juvenile grass shrimp and killifish. Bull. Environ. Contam. Toxicol. 44 776-783. 

Dot Marking Toxic liquids, n.o.s. Dichloro-(2-chlorovinyl)arsine UN 2810 Dot Placard Poison... 

Brock, W.J., H.J.Trochimowicz, R.J.Millischer, C.Farr, T.Kawano, and G.M. Rusch. 1995. Acute and subchronic toxicity of 1,1-dichloro-l-fluoroethane (HCFC-141b). Fd. Chem. Toxicol. 33 483 190. 

The hydroxylation of the ring moiety of 2,4-D similarly converts the parent herbicide to a non-toxic product. Microorganisms may bring about such a detoxification when they hydroxylate the ring in the 4-position, a process that leads to a migration of the chlorine to give 2,5-dichloro-4-hydroxyphenoxy-acetic acid. 

Pesticides containing methyl or other alkyl substituents maybe linked to N or 0 (i.e., N- or O-alkyl substitution). An N- or O-dealkylation catalyzed by microorganisms frequently results in loss of the pesticide activity. Phenylurea (see Chap. 1) becomes less active when microorganisms AT-demethylate the molecules (e. g., the conversion of Diuron to the normethyl derivative, Fig. 7). The subsequent removal of the second AT-methyl group renders the molecule fully nontoxic [169]. On the other hand, the microbial O-demethylation of Chloroneb creates the non-toxic product 2,5-dichloro-4-methoxyphenol (Fig. 7). 

Chemical/Physical. Saleh and Casida (1978) demonstrated that toxicant B 2,2,5-endo,6-exo,8,9,10-heptachlorobornane), the most active component of toxaphene, underwent reductive dechlorination at the geminal dichloro position, yielding 2-endo,5-endo,6-exo,8P,lO-hexn-chlorobornane, and 2-evo,5-e/3c/o,6-evo,8,9,10-hexachlorobornane in various chemical, photo-... 

Immunological and Lymphoreticular Effects. No studies were loeated regarding immunological and/or lymphoreticular effects in humans or animals following exposure to 3,3 -diehlorobenzidine by any route of exposure. The immime system does not appear to be a sensitive target of 3,3 -dichlorobenzidine toxicity. Consequently, immune system disruptions are not expected in humans exposed to 3,3 -dichloro-benzidine at the levels at which it occurs at hazard waste sites. 

A susceptible population is defined as one which will exhibit a different or enhanced response to a chemical compared to most persons exposed to the same level of exposure. Reasons may include genetic makeup, age, health and nutritional status, and exposure to other toxic substances (e g., cigarette smoke). For this chemical, these parameters may result in reduced detoxification or excretion of 3,3 -dichloro-benzidine, or compromised function of target organs affected by 3,3 -dichlorobenzidine. Populations who are at greater risk due to their unusually high exposure to 3,3 -dichlorobenzidine are discussed in Section 5.6, Populations With Potentially High Exposure. 

Reproductive Toxicity. No studies were foimd regarding reproductive toxicity of 3,3 -dichloro-benzidine. Should data suggesting that reproductive organs are affected in a 90-day study become available, multigenerational reproductive studies in animals may be warranted. 

Developmental Toxicity. No studies were found regarding developmental toxicity of 3,3 -dichloro-benzidine in humans. Animal studies have shown that 3,3 -dichlorobenzidine and/or metabolites may be transferred across the placenta and or through maternal milk to the offspring and may affect the growth of the kidneys after parenteral exposure during pregnancy (Golub 1972 Shabad et al. 1972) or induce... 

Table 4-1 lists the facilities in each state that manufacture 3,3 -dichlorobenzidine or process the compound for further distribution, the range of maximum amounts of 3,3 -dichlorobenzidine on-site, and the activities and uses of the product. Processing means the further distribution of the compound either as the same physical compound, in a different form or physical state, or as part of another article or mixture (40 CFR 372.3). In 1996, there was one facility in the United States that manufactured or used 3,3 -dichloro-benzidine. The data listed in Table 4-1 are derived from the 1996 Toxics Release Inventory (TRI96 1998). Only certain types of facilities were required to report. Therefore, this is not an exhaustive list. 

According to the Toxics Release Inventory (TRI), in 1996, a total of 2 pounds (1 kg) of 3,3 -dichloro-benzidine was released to the environment from one processing facility (TRI96 1998). Table 5-1 lists amounts released from this facility. In addition, an estimated 250 pounds (118 kg) were released by manufacturing and processing facilities to publicly owned treatment works (POTWs), and an estimated 51,550 pounds (23,432 kg) were transferred offsite (TRI96 1998). The TRI data should be used with caution because only certain types of facilities are required to report. Therefore, this is not an exhaustive list. 

The reaction of the lipid-regulator gemfibrozil with free chlorine yielded four chlorinated derivatives of this compound [94]. Chlorination of acetaminophen (paracetamol) generated 11 discernible DBFs, including the toxic compounds 1,4-benzoquinone and A-acetyl-p-benzoquinone imine and two ring chlorination products, chloro-4-acetamidophenol and dichloro -acetamidophenol [95]. 

Cyanobacteria toxins are toxins produced by certain species of blue-green algae that have become a major environmental and public health concern. The behavior of cyanotoxins during chlorination treatment has been recently reviewed by Merel et al. [129]. Chlorination DBFs have been reported only for the hepatotoxins microcystin-LR and cylindrospermopsin. Other cyanotoxins, such as nodularins, saxitoxins, and anatoxins, have yet to be investigated. Different isomers of six chlorination products of microcystin-LR have been characterized dihydroxy-microcystin, monochloro-microcystin, monochloro-hydroxy-microcystin, monochloro-dihydroxy-microcystin, dichloro-dihydroxy-microcystin, and trichloro-hydroxy-microcystin. Only two chlorination DBFs have been reported so far for cylindrospermopsin 5-chloro-cylindros-permopsin and cylindrospermopsic acid [129]. Chlorination of microcystin, cylindrospermopsin, and nodularins seems to reduce the mixture toxicity however, this aspect has not been extensively studied [129]. 

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