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Dieldrin

DESIGNATIONS

CAS No.: 60-57-1
Systematic name: Dieldrin
Chemical name: 1,2,3,4,10,10-Hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4,5,8-dimethanonaphthalene
Synonyms, Trade names:
Alvit, Heod, Compound 497, Octalox, ENT 16,225
Chemical name (German):
Dieldrin; 1,2,3,4,10,10-Hexachlor-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4,5,8-dimethanonaphthalin
Chemical name (French):
Dieldrine
Appearance:
white, odourless crystals

BASIC CHEMICOPHYSICAL DATA

Empirical formula: C12H8Cl6O
Rel. molecular mass: 380.91 g
Density: 1.70 g/cm3
Boiling point: (decomposition)
Melting point: 176-177C
Vapour pressure: 24 x 10-6 Pa at 25C
Solvolysis/solubility: in water: 0.1 mg/l

miscible with petroleum, acetone and aromatic compounds

Conversion factors: 1 ppm = 15.8 mg/m3

1 mg/m3 = 0.06 ppm

ORIGIN AND USE

Usage:
Dieldrin is an insecticide used in particular to protect cotton plants.

Origin/derivation:
Dieldrin is produced by epoxidation of aldrin, a process which also occurs naturally.

Toxicity

Humans: LD50 64 mg/kg (estimated) acc. MERCIER, 1981
Mammals:
Rat: LD50 46-63 mg/kg, oral acc. VERSCHUEREN, 1983
  LD50 52-117 mg/kg, dermal acc. VERSCHUEREN, 1983
Mouse: LD50 38-77 mg/kg, oral acc. MERCIER, 1981
Dog: LD50 56-120 mg/kg, oral acc. MERCIER, 1981
Rabbit: LD50 45-50 mg/kg, oral acc. MERCIER, 1981
Cow: LD50 25 mg/kg, oral acc. MERCIER, 1981
Aquatic organisms:
Cyprinodont LC50 5 ppb (96 h) acc. VERSCHUEREN, 1983
Mugilidae LC50 23 ppb (96 h) acc. VERSCHUEREN, 1983
American minnow LC50 16 mg/l (96 h) acc. VERSCHUEREN, 1983
Blue perch LC50 8 mg/l (96 h) acc. VERSCHUEREN, 1983
Rainbow trout LC50 10 mg/l (96 h) acc. VERSCHUEREN, 1983
Water flea LC50 250 mg/l (48 h) acc. VERSCHUEREN, 1983
Crawfish LC50 460 mg/l (96 h) acc. VERSCHUEREN, 1983
Insects:
Pteronarcys california LC50 0.5-39 g/l (96 h) acc. VERSCHUEREN, 1983

Characteristic effects:

Humans/mammals: Dieldrin can cause poisoning following resorption via the skin, oral intake or inhalation. It acts as a stimulant to the central nervous system and accumulates in fatty tissue causing severe damage to the liver and kidneys. Animal experiments have revealed a carcinogenic effect, but as yet no teratogenic action.

Plants: Dieldrin does not have a toxic effect on plants (MERCIER, 1981).

ENVIRONMENTAL BEHAVIOUR

Water:
Accumulation takes place in aqueous systems on account of the good solubility of the substance. Dieldrin is assigned in Germany to water hazard class 3 (highly water-polluting) as a result of the high toxicity in aquatic organisms.

Soil:
Dieldrin accumulates in soils depending on their texture and water content.

Half-life:
Roughly 95 % of an applied quantity of between 3.1 and 5.6 kg/ha disappears from the soil after 12.8 years on average. Only some 9 % evaporates out of loamy or sandy soils in 60 days. Between 75 and 100 % of dieldrin is degraded or decomposed in 3 - 25 years [VERSCHUEREN, 1983].

Environmental behaviour

Degradation, decomposition products:
Dieldrin is metabolised in the body to form 1,2-dihydroxy-dieldrin and 4,5-aldrin-trans-dihydrodial. UV light causes decomposition to form CO2.

Food chain:
Dieldrin accumulates in fatty tissue and in the mammary glands of human (WIRTH, 1981).

ENVIRONMENTAL STANDARDS

Medium/ acceptor Sector Country/ organ.

Status

Value Cat. Remarks Source
Water: Drinkw D

L

0.1 g/l   single substance acc. RIPPEN, 1992
Drinkw D

L

0.5 g/l   sum of pesticides acc. RIPPEN, 1992
Drinkw EC

L

0.1 g/l   single substance acc. RIPPEN, 1992
Drinkw EC

L

0.5 g/l   sum of pesticides acc. RIPPEN, 1992
Drinkw USA

G

1 g/l   In state of Illinois acc. WAITE, 1984
Soil:   NL

G

0.5 g/kg   Single substance, Reference acc. TERRA TECH 6/94
  NL

L

2.5 g/kg   Aldrin+Dieldrin+Endrin Intervention acc. TERRA TECH 6/94
Air: Workp D

L

0.25 mg/m3 MAK Skin DFG, 1989
Workp SU

(L)

0.01 mg/m3   Skin acc. KETTNER, 1979
Workp USA

(L)

0.25 mg/m3 TWA Skin ACGIH, 1986

Note:
There has been a total ban on the use of dieldrin in the Federal Republic of Germany since 1988 (Order Governing Use of Pesticides).

Comparison/reference values

Medium/origin Country Value Source
Surface/groundwater
Irish Sea (suspension) IRL 0.2-140 ng/g acc. VERSCHUEREN, 1983
Hawaii (sediment) USA 2-39.5 ppb acc. VERSCHUEREN, 1983
Los Angeles (harbour) USA 0.6 x 4.5 ppb acc. VERSCHUEREN, 1983
Western Baltic (surface)   0.17x10-9 g/l acc. VERSCHUEREN, 1983
North Sea, SE England/Holland   0.4-17 ppb (1974-76) acc. VERSCHUEREN, 1983

Assessment/comments

Dieldrin is a highly toxic substance towards aquatic organisms and is highly persistent in the environment. In addition, it accumulates in fatty tissue and can also cause severe poisoning in humans. Therefore, its use should be restricted as far as possible.


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