About POPS

Eng: pentachlorobenzene

CAS Number: 608-93-5

Formula: C6HCl5

Molecular weight: 250.34 g/mol

Density: 1.609 g/cm3

Boiling point: 275-277°C

Melting point: 86 °C

Water solubility at 20 °C: insoluble

Pentachlorobenzene is a pesticide, industrial chemical and by-product. It is found as an incidental impurity in several pesticides, including pentachloronitrobenzene, clopyralid, atrazine, chlorothalonil, dachal, lindane, pentachlorophenol, picloram and simazine.

Pentachlorobenzene is highly persistent in the environment, bioaccumulative and can be transported over long distances. It is moderately toxic to humans and highly toxic to aquatic organisms.

Pentachlorobenzene is inadvertently produced and released into the environment by incinerators, municipal waste incinerators, pulp and paper mills using chlorine bleaching, steel mills, petroleum refineries and in activated sludge from wastewater treatment plants.

Pentachlorobenzene was used as a pesticide and antipyrene and in combination with polychlorinated befinyls in dielectric fluids for electrical equipment.

Eng: Polychlorinated biphenyls

CAS Number: 1336-36-3 (Polychlorinated biphenyls with different chlorine content in the biphenyl molecule have different CAS registration numbers)

Formula: C12H(10-n)Cln, where n equals from 1 to 10 (e.g., PCB 146, 2,2,3,4,5,5-hexachlorobiphenyl – C12H4Cl6)

Molecular weight: 360.88 g/mol

Density: 1.593 g/cm3

Boiling point: 436.6 °C

Water solubility at 20 °C: 0.01 – 0.0001 ug/l

PCBs are the most resistant chemicals. The physical and chemical properties that made PCBs useful in industry have made them one of the most dangerous environmental pollutants. With thermal and chemical stability, PCBs have proven to be extremely resistant to natural factors.

PCBs enter the environment in various ways, both due to modern industrial applications of PCBs and to their possible by-formation. PCBs can be released into the environment from technical products, transformers, capacitors, varnishes, paints, chemicals, building materials, etc. Entering the environment, PCBs are distributed to all components (air, water, soil, etc.). PCBs, like the vast majority of POPS, accumulate in the adipose tissues of animals.

Polychlorinated biphenyls are substances that were used for a long time as a dielectric or coolant in electrical equipment, as plasticizers and other additives in the production of varnishes, paints, lubricating oils, hydraulic fluids, etc.

Eng: tetrabromodiphenyl ether and pentabromodiphenyl ether

CAS Number. Tetrabromodiphenyl ether: 5436-43-1

CAS Number. pentabromodiphenyl ether: 32534-81-9

Formula: C12H6Br4O (Tetrabromodiphenyl ether), C12H5Br5O (pentabromodiphenyl ether)

Molecular weight: 485.79 g/mol (Tetrabromodiphenyl ether), 564.69 g/mol (pentabromodiphenyl ether)

Ether molecules are released into the environment during production and use in consumer products. They can be present in the air in the form of suspended particles, when dust settles, as well as with snow or rain, they fall on the soil or water. The disintegration of ether molecules in the soil is very slow; they can remain in the soil for several years. Toxicological studies have shown reproductive toxicity and effects on humans (thyroid hormones, reproductive system, etc.) and animals. They are highly resistant in the environment, bioaccumul ative, capable of long-range travel.

Tetrabromodiphenyl ether and pentabromodiphenyl ether were used as antipyrene (a fire retardant).

Eng: toxaphene

CAS Number: 8001-35-2

Formula: Medium formula C10H10Cl8 (from C10H11Cl5 to C10H6Cl12)

Molecular weight: medium formula has g/mol value

Molecular weight: 170.68 g/mol

Density: 1.65 g/cm3

Melting point: 65-90 °C

Water solubility at 20 °C: insoluble

Toxaphene (also known as camphechlor) is a yellow-to-amber, waxy solid. It is considered to have high toxicity and ability to accumulate in environment. Toxaphene effects on CNS, endocrine system and results in morphological changes in the liver and kidney.

Insecticide is used for pest control on cotton, grains, fruits, nuts and vegetables crops. It is also used as a remedy against various types of ticks in pets, as well as to control pests in livestock.

Eng: endosulfan

CAS Number: 115-29-7 (alpha-endosulfan 959-98-8, beta- endosulfan 33213-65-9)

Formula: C9H6Cl6O3S

Molecular weight: 406.93 g/mol

Density: 1.8 g/cm3

Melting point: 80 °C

Water solubility at 20 °C: 0.32 mg/l

Technical endosulfan is a mixture of two isomers along with small amounts of impurities. Endosulfan is highly toxic to aquatic organisms, amphibians, reptiles, birds, bees, worms, microorganisms, and is incompatible with complex pest control measures.

It has a high acute toxicity, but the chronic toxicity of endosulfan for mammals is lower than that of other diene synthesis drugs based on hexachlorocyclopentadiene. Exposure to endosulfan has been the cause of many workplace deaths due to accidental exposure and self-poisoning.

The consequences of chronic human exposure to endosulfan include human birth defects, congenital anomalies of reproductive system, chronic brain damage, recurrent seizures, epilepsy, autism, delayed puberty, endometriosis, menstrual irregularities, early menstruation, breast enlargement in men, various cancers diseases, congenital mental development problems, cerebral palsy, psychiatric disorders, visual impairment and loss.

Endosulfan was used as a broad spectrum insecticide. It was used to control sucking, chewing, and drilling insects on vegetables, fruits, grains, cotton, tea, and ornamental shrubs, vineyards, and trees.

Eng: hexabromocyclododecane

CAS Number: 3194-55-6 (25637-99-4)

Formula: C12H18Br6

Molecular weight: 641.7 g/mol

Density: 2.1 g/cm3

Melting point: 188 °C

Hexabromocyclododecane is an industrial chemical. HBCD is highly persistent and has high bioaccumulation potential. It is extremely toxic to aquatic life. Laboratory studies on mammals discover that HBCD negatively affects liver and thyroid gland; it can also lead to the development of neurotoxic effects even at low doses of exposure.

Mainly used as antipyrene in swelling and release polystyrene, especially in polystyrene-treated thermal insulation boards in construction and transport. It was also used in textile coatings and high-strength polystyrene electrical and electronic equipment.

Eng: hexachlorobutadiene

CAS Number: 87-68-3

Formula: C4Cl6

Molecular weight: 260.76 g/mol

Density: 1.68 g/cm3

Melting point: -19 °C

HCBD is a highly toxic pesticide. It is resistant to the environment and is found in various ecological niches. It has a high bioaccumulation potential. Due to its physical and chemical properties and half-life in the atmosphere, it persists for a long time and is transported over long distances from its sources. HCBD is highly toxic to aquatic organisms and damages the kidney of mammals.

Industrial chemical is a by-product. It was used as an insecticide for grape phylloxera control. It also has fumigation and herbicidal properties. Highly purified hexachlorobutadiene is also used in the electrical industry as an integral part of fluids for transformers.