Organochlorine pesticides heptachlor

A second organochlorine pesticide, heptachlor (HEP), a chlorinated cyclodiene that was used primarily as an agricultural and domestic insecticide, was evaluated for its potential to suppress the immune system of rats. Rats were exposed to HEP pre-and postnatally, as described above for MXC. The IgM antibody response to SRBCs was suppressed at all doses in males but not females at 8 weeks of age. At 26 weeks of age, the IgG anti-SRBC response was suppressed in all of the HEP-exposed males, but not females.131... 

E.A. Maier., L.G.M.Th. Tuinstra., A.H. Roos and B. Griepink, Certification of the contents (mass fraction) of organochlorine pesticides (heptachlor, -heptachlorepoxide, y-chlordane, a-endosulfan, aldrin, dieldrin, endrin. o,p -DDT and p.p -DDT) inanimal feed— CRM 115. Report EUR 16889EN, European Commission, Luxembourg (1996). 

Williams, G.M. and S. Numoto. 1984. Promotion of mouse liver neoplasms by the organochlorine pesticides chlordane and heptachlor in comparison to dichlorodiphenyltrichloroethane. Carcinogenesis 5 1689-1696. 

Telang S, Tony C, Williams GM. 1982. Epigenetic membrane effects of a possible tumor promoting type on cultured liver cells by the non-genotoxic organochlorine pesticides chlordane and heptachlor. Carcinogenesis 3 1175-1178. 

Lindane (gamma-hexachlorocyclohexane) is one of the last of the old style organochlorine pesticides still in use. Use of organochlorines such as DDT, aldrin, dieldrin, heptachlor, and toxaphene is restricted or banned in many countries because of their persistence in the environment, bioaccumulation, and toxicity. Lindane was first isolated in 1825 along with other similar compounds, but its deadly effects on insects were not recognized until the 1940s. 

Heptachlor epoxide Pesticide - organochlorine - bioaccumulates - heptachlor epoxide is a breakdown product of heptachlor, an insecticide from 1953 to 1974 in US on a wide range of insects. Most use canceled in 1974 and importation and manufacture prohibited in the US, use banned in 1988... 

Organochlorine pesticides are defined as fat soluble. Most have a log Pm. over 5 (aldrin, DDE, DDT, dieldrin, endrin, and heptachlor), and the HCH isomers have a log Pm. in the 3-4 range. The majority of the OPPs are also classified as fat soluble but present lower values of log Pow. Chlorfenvinphos, fenitrothion, and diazinon, with a log P[Pg.718]

Fig. 2.9. Historical usage amounts of each organochlorine pesticides DDTs, CHLs, Al-drin, Endrin, Toxaphene, and Heptachlor from KMOE (2004c), HCHs from Lee (1982), and Endosulfan from Lee (1982) by 1980 and modified from Jeong et al. (2001c) since 1981. Total endosulfan use of five years (from Jeong et al. (2001c)) was converted to annual average amount.

Organochlorine pesticides were predominantly used during the 1950s-1970s in China. DDT, HCH, toxaphene, HCB, chlordane, heptachlor, and mirex used to be produced in China. Historically, there have been 60 POP pesticide-producing enterprises, which were located in 18 provinces in China. 

In 1997, the United Nations Environment Programme (UNEP) Governing Council decided that immediate international action should be taken to protect human health and the environment. International negotiations to reduce and eliminate the emission and discharges of an initial set of 12 POPs were initiated at the Stockholm Convention on POPs in May 2001. The 12 substances that were addressed at the Stockholm Convention were aldrin, endrin, dieldrin, dichlorodiphenyltrichoroethanes (DDTs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), chlordane, toxaphene, heptachlor, hex-achlorobenzene (HCB) and mirex. Basic information and status of major organochlorine pesticides in China are summarized in Table 8.1. 

Chlordane was introduced as an insecticide in 1945 and was the first cyclodiene insecticide that was used in agriculture (Eisler, 1990). It was the second most important organochlorine pesticide after toxaphene from 1976 to 1977 (Stansley Roscoe, 1999). It has been used on agricultural crops and extensively in the control of termites (Smith, 1991). Chlordane and heptachlor can be metabolized into two persistent (oxygenated) epoxides—oxychlordane and heptachlor epoxide—in mammals (Nomeir Hajjar, 1987) such that the two compounds are always measured together with chlordane and heptachlor. 

A survey on the levels of organochlorine pesticides in human milk from Hmong hill tribes in northern Thailand (Stuetz et al., 2001) reported considerable levels of heptachlor (125 ngg-1 lipid), heptachlor epoxide... 

Pesticides are toxic chemicals. Organochlorinated pesticides, because of their high persistence, have been identified in tissues of animals and humans. Insecticides (e.g., DDT and heptachlor) have been found in the milk and body fluids of humans and have caused global concern. Proper care and disposal of organochlorinated pesticides by qualified and trained workers under proper management is the answer to achieve human safety and to contain chemical toxicity. 

Two organochlorine pesticides have also been evaluated in animal models using early life stage exposures. Methoxychlor (Chapin et al., 1997) and heptachlor (Smialowicz et al., 2001) were evaluated for immunotoxicity after perinatal plus juvenile exposure of rats. In the case of methoxychlor, T cell-dependent antibody responses were depressed persistently in males but not females (Chapin et al., 1997). For heptachlor, early exposure of Sprague-Dawley rats, using doses relevant to human exposure, produced persistent impairment of antibody responses in males but not females. No adult-exposure immunotoxicity was observed at the doses examined, suggesting that there is an increased susceptibility of the prenatal and/or early postnatal life stages to this pesticide (Smialowicz et al., 2001 Smialowicz, 2002). 

A variety of methods has been devised for the confirmation of heptachlor residues (Table II). The presence in the heptachlor molecule (Figure 1) of a reactive allylic chlorine atom has been the basis of three confirmatory tests based on its ease of replacement. Reaction with a silver acetate-glacial acetic acid mixture produced 1-acetoxychlordene which, with the GLC conditions used, had a retention time close to heptachlor epoxide 44). Of the common organochlorine pesticides, only heptachlor reacted quantitatively. Endrin reacts to a small extent with the glacial acetic acid to give a secondary endrin ketone peak. When the reaction of heptachlor with silver salts was extended to silver carbonate in aqueous alcohol, 1-hydroxychlordene was obtained which can easily be converted to the more volatile and GG-responsive silyl ether. Unfortunately, this silyl ether has a Rt identical to aldrin. With silver carbonate, hepta-... 

A large number of ubiquitous environmental pollutants are very toxic to the hypothalamic-pituitary-thyroid (HPT) axis when administered at high (greater than environmental) levels. To study low level effects on the HPT axis, laboratory animals were administered a mixture of 16 organochlorine pesticides and other chlorinated hydrocarbons and heavy metals, all at levels similar to those found environmentally, so as to simulate environmental exposure. The chemicals included DDT (6.91), HCB (5.73), TCDD (6.80), PCBs (6.29), methoxychlor (5.08), endosulfan (3.83), heptachlor (6.10), hexachlorocyclohexane (3.80), dieldrin (5.40), aldrin (6.50), mirex (7.18), several chlorinated benzenes (2.84-3.44), cadmium (-1.65), and lead (1.35). Effects were measured by monitoring thyroid activity. The study found that this mixture of environmental pollutants was toxic and can alter HPT physiology in sexually mature malesJ50 ... 

The trace enrichment of pesticides from groundwater is a straightforward problem for reversed-phase SPE. The following example uses the EMPORE disk (C-18) to isolate organochlorine pesticides including aldrin, chlordane, endrin, heptachlor, lindane, methoxychlor, pentachlorophenol, and toxaphene from groundwater (Fig. 4.15). 

Pigs were fed for 14 weeks with feed enriched with organochlorine pesticides (OCPs). The pesticides used were pure calibrants of HCB, a-HCB, b-HCB, y-HCB, heptachlor, dieldrin, endrin, and p,p -DDT. Quantities of 100 mg to 1.8 g of these compounds were weighed and dissolved in hexane/maize oil. For b-HCB, acetone/maize oil was used. The desired amounts were calculated using maximum levels for fat applicable in EC... 

The samples collected during the short rain season showed the highest levels of pesticide residues, of which the residues of p,p -DDT, HCH, dieldrin and heptachlor were the highest detected organochlorine pesticides (Figure 12). 

Figure 7.11 Results obtained for the supercritical extraction of various organochlorine pesticides from contaminated soil and Celite , showing the influence of (a) the soil matrix, and (b) the soil organic matter (SOM) content A, lindane B, aldrin C, dieldrin D, heptachlor E, isodrin (a) B, Celite , soil (b) B, SOM 0.2% , SOM 15% W, SOM 35% [4] (cf. DQ 7.8).

Organochlorine pesticides include aldrin, chlordane, dichophane (DDT), dieldrin (also a metabolite of aldrin) endrin heptachlor, hexachlorobenzene (EICB), 1, 2, 3, 4, 5, 6-hexachlorocyclohexane (EICEI = benzenehexachloride, BE1C), and lindane (gamma - EICEI). These compounds were widely used but persist in the environment, and lindane, which has a relatively short half-life in vivo, is now the only member of this group still in common use. Pentachlorophenol is used as a contact herbicide. This compound is still widely used in wood preservatives and disinfectants. 

It is well established that organochlorine pesticides, such as DDT, dleldrin, aldrin, heptachlor and chlordane, can cause tumors in rodents, particularly liver cancer in mice. A number of investigations have sought to determine whether these pesticides are carcinogenic to humans. 

At present, the pesticide soil monitoring is carried out by the Ministry of Environment and Waters (MoEW), has started in 1997 and covers the whole country. In the scope of the monitoring programme are the following persistent organochlorine pesticides aldrin, DDT, dieldrin, endrin, heptachlor, hexachlorbenzene (HCB), methoxychlor, cis-heptachlorepo-xide, alfa-HCH and lindane. 

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