Organochlorine pesticides aldrin

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. 

Secondary air contamination is caused because pesticides on plant and soil surfaces convert into steam, or disperse by adsorbing on dust particles. Under certain conditions, up to 50% of such OCRs (organochlorine pesticides) as DDT, aldrin, and dieldrin move into the air during the week after a field is treated. DDT evaporates from a treated field at a rate of 10-50 kg/ha a year, depending on temperature, humidity, and air movement [3]. On the second or third day after treatment, OPP concentrations can be higher than on the first day as a result of pesticides converting into steam [22]. 

Wilson and co-workers [332, 333] have discussed the determination of aldrin, chlordane, dieldrin, endrin, lindane, o,p and p,p isomers of DDT and its metabolites, mirex, and toxaphene in seawater and molluscs. The US environmental Protection Agency has also published methods for organochlo-rine pesticides in water and wastewater. The Food and Drug Administration (USA) [334] has conducted a collaborative study of a method for multiple organochlorine insecticides in fish. Earlier work by Wilson et al. [333, 335] in 1968 indicated that organochlorine pesticides were not stable in seawater. 

The specific mechanism by which chlordecone is transferred from the gut, lungs, or skin to the blood is not known. However, the preferential distribution of chlordecone to the liver rather than the fat tissues suggests that it may be transported in the plasma differently from other organochlorine compounds (Soine et al. 1982). In vitro and in vivo studies of human, rat, and pig plasma showed that chlordecone is preferentially bound by albumin and high-density lipoproteins (HDL), which may explain its tissue distribution. Other organochlorine pesticides such as aldrin and dieldrin bind to very-low-density lipoproteins (VLDL) and low-density lipoproteins (LDL) and distribute preferentially to fat (Soine et al. 1982). 

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. 

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]

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. 

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-... 

Fig. 4.29. Extraction-time profile curves (signal height versus absorption time) for organochlorine pesticides in aqueous solutions. Conditions spiking level 0.2-1.2 ng/ml polydimethylsiloxane fibre length 100 pm magnetic stirring rate 250 rpm. Although equilibrium was not reached for some analytes, the extraction time was chosen to be 15 min. ( ) a-hexachlorocyclohexane, ( ) /3-hexa-chlorocyclohexane, (A) dieldrin, (x) aldrin, (O) 4,4 -DDT, ( ) 4,4 -DDE, ( + ) 4,4 -DDD and ( ) endosulfan sulphate. (Reproduced with permission of Elsevier.)...

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). 

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). 

Mitema and Gitau reported low levels of a-BHC, P-BHC, aldrin, dieldrin, lindane and p,p -DDT in Nile perch from Lake Victoria. The p,p -DDT and its metabolites formed the largest proportion of the organochlorine pesticide residues in the fish samples. The presence of these residues was attributed to the previous use of the pesticides in agriculture and aerial control of mosquitoes in the Lake Victoria region. Studies conducted in other parts of the country revealed similar trends of pesticide contaminations. Wandiga reported residues of aldrin, a-endosulfan, dieldrin, endrin, DDT, DDE, DDD and lindane in seawater, seaweeds, sediments, and fish. They found residue levels ranging from 0.503-9.025 ng/g in sea water, 0.584-59.00 ng/g in sediments, and concentrations of 1011 ng/g and 418 ng/g of p,p -DDT and p,p -DDD, respectively, in fish. 

The residues of dieldrin were the highest of all the organochlorine pesticides analysed, with concentrations ranging from 36.42 and 43.4 pg/kg. Compared with the values detected for aldrin, whose concentration ranged between 25.16 and 30.36 pg/kg, the high levels of dieldrin were attributed to degradation of the latter. 

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. 

Most organochlorine pesticides are now banned (DDT, aldrin, endrin, dieldrin, chlordane, heptachlor, lindane, toxophene and hexachlorobenzene), or severely restricted in developed countries, but they are still used in developing countries. 

The sum for all organochlorinated pesticides identified in water (a, p, y-HCH, heptachlor, aldrin, DDE, dieldrin and DDT) usually exceeds the maximum acceptable concentration (MAC). 

The acute toxic symptoms of many chlorinated pesticides include headache, dizziness, loss of coordination, nausea, vomiting, tremors, and convulsions. Many organochlorine pesticides, such as DDT, aldrin, dieldrin, endrin, mirex, and kepone were found to be... 

Hematological Effects. A questionnaire survey revealed that 4% of persons living in homes treated with chlordane to control termites reported anemia as a chronic effect (Menconi et al. 1988). The effect cannot be attributed to chlordane alone, because the quantitative amounts of aldrin and heptachlor were combined with the chlordane measurement in the analysis of indoor air. A number of anecdotal reports of blood dyscrasia associated with organochlorine pesticides (chlordane. 

We now introduce some recently reported and interesting research that reinforces the basic concepts of LLE. Cantwell and eo-workers have introduced the concept of a true LLE that has been downsized to a micro extraction scale (17). In the past, the eoneept of a miero-LLE, abbreviated /xLLE, as introdueed by the EPA and promulgated through their 500 series of methods, was designed to conduct TEQA on samples from sources of drinking water. Method 508 required that 35 mL of groundwater or tap water be placed in a 40 mL vial and extraeted with exaetly 2 mL of hexane. Organochlorine pesticides such as aldrin, alachlor, dieldrin, heptachlor, and so forth are easily partitioned into the hexane. A l-/xL aliquot is then injected either manually or via autosampler into a GC-ECD to achieve... 

Because the period of pesticide stability in water and soil depends on many different factors (e.g., variations in pH of water and soil, bacterial content, plant and animal content, temperature, humidity, and degree of solar radiation), this classification is largely conventional. It does, however, permit the definition of many organochlorine pesticides (DDT, hexachlorocycyclohexane, aldrin, diel-drin, heptachlor and others) as very persistent (Table 1). 

---