Heptachlor

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General
Surname Heptachlor
other names

1,4,5,6,7,8,8-heptachlor-3a, 4,7,7a-tetrahydro-4,7-methanoindene

Molecular formula C 10 H 5 Cl 7
Brief description

white solid with a camphor- like odor

External identifiers / databases
CAS number 76-44-8
EC number 200-962-3
ECHA InfoCard 100,000,876
PubChem 3589
Wikidata Q417891
properties
Molar mass 373.32 g mol −1
Physical state

firmly

density

1.58 g m −3 (9 ° C)

Melting point

95-96 ° C

boiling point

145 ° C (2 hPa)

Vapor pressure

0.053 Pa (25 ° C)

solubility

poor in water (<1 g l −1 at 20 ° C)

safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary
06 - Toxic or very toxic 08 - Dangerous to health 09 - Dangerous for the environment

danger

H and P phrases H: 300 + 310-351-373-410
P: 264-273-280-301 + 310-302 + 350-310
MAK

DFG / Switzerland: 0.05 mg m −3 (measured as inhalable dust )

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Heptachlor is an insecticide that acts as a contact or food poison . It was primarily against soil insects and termites , sometimes against Anopheles -Mücken as malaria -Überträger as well as pesticides used.

In humans, heptachlor leads to liver damage and overstimulation of the central nervous system . It is suspected of causing cancer . The half-life in the soil is up to two years.

Synthesis and composition

Heptachlor is represented by a reaction of hexachlorocyclopentadiene with cyclopentadiene , in which chlorodene is formed as an intermediate product. This is chlorinated in the dark and with the addition of fuller's earth to make technical heptachlor .

Synthesis of heptachlor

Technical heptachlor consists of a complex mixture of different components. For the most part, the mixture is composed of 72% of the two enantiomers (+) - and (-) - heptachlor, furthermore 18% are trans - chlordane , 2% cis -chlorordane, 2% nonachlor, 1% chlordene, 0.2% Hexachlorbuta-1,3-diene and 10 to 15 other components.

  • Main components of heptachlor

  • (-) - heptachlor

  • (+) - heptachlor

  • trans -Chlordane

Analytical evidence

The chemical-analytical detection in environmental samples, food and animal feed is carried out after suitable sample preparation to separate the matrix and gas chromatographic separation of minor components by high-resolution mass spectrometry techniques such as flight mass spectrometry (Time-of-Flight mass spectrometry).

Heptachlor epoxide

Heptachlor is oxidized biotically and abiotic to heptachlor epoxide. This is more stable than heptachlor and is also broken down more slowly. The abiotic degradation creates a racemic mixture of (-) - and (+) - heptachlorepoxide, while heptachlor is mainly converted into the (+) - enantiomer in the metabolism.

Reaction of heptachlor (middle) to heptachlor epoxide (left) or photoheptachlor (right)

Prohibition

In Stockholm Convention of 22 May 2001 for a worldwide ban on the manufacture, sale and use of twelve was persistent organic pollutants ( POP = persistent organic pollutants ) ratified. That " dirty dozen " includes heptachlor. On May 17, 2004, following ratification by the 50th Accession State, the Convention became globally valid.

No plant protection products containing this active ingredient are permitted in the EU or Switzerland .

In Germany, the limit of 30 ng per liter for heptachlor and its epoxide in drinking water may not be exceeded in accordance with the Drinking Water Ordinance, the maximum amount for (plant-based) food is 10–100 µg / kg.

literature

Web links

Individual evidence

  1. ↑ a b c d e f g h Entry on heptachlor in the GESTIS substance database of the IFA , accessed on January 10, 2017(JavaScript required) .
  2. ↑ International Chemical Safety Card (ICSC) for heptachlor at the National Institute for Occupational Safety and Health (NIOSH), accessed January 13, 2016.
  3. ↑ Entry on heptachlor in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
  4. ↑ Swiss Accident Insurance Fund (Suva): Limit values ​​- current MAK and BAT values (search for 76-44-8 or heptachlor ), accessed on November 2, 2015.
  5. ^ A b c Opinion of the Scientific Panel on contaminants in the food chain [CONTAM] related heptachlor as an undesirable substance in animal feed . In: EFSA Journal . tape 5 , no. 6 , 2007, p. 478 , doi : 10.2903 / j.efsa.2007.478 .
  6. ↑ Eric J. Reiner, Adrienne R. Boden, Tony Chen, Karen A. MacPherson and Alina M. Muscalu: Advances in the Analysis of Persistent Halogenated Organic Compounds . In: LC GC Europe . 23 (2010) 60-70.
  7. ↑ General Directorate Health and Food Safety of the European Commission: Entry on heptachlor in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on March 26, 2016.
  8. ↑ Ordinance on the quality of water for human consumption (Drinking Water Ordinance - TrinkwV 2001 , Annex 2 (to Section 6, Paragraph 2) Part I.
  9. ↑ Gerhard Eisenbrand (Ed.) And Peter Schreier (Ed.): RÖMPP Lexikon Lebensmittelchemie . 2nd revised edition, 2006; Georg Thieme Verlag; P. 498.