Volatile organic compounds
Volatile Organic Compounds ( English volatile organic compounds , short VOC ) is the collective term for organic , that carbonaceous pass substances at room temperature or higher temperatures by evaporation (colloquially "evaporation") in the gas phase, ie volatile shown. The gas methane , CH 4 , is often not included, sometimes explicitly excluded by the abbreviation NMVOC ( n on- m ethane v olatile o rganic c ompounds ).
The term condensable organic compounds , abbreviated to COC , describes the same compounds; this alternative term is only used in connection with condensation processes.
Definitions
The word volatile implies that substances belonging to the group of VOCs evaporate (volatilize) quickly due to their high vapor pressure or low boiling point .
According to the World Health Organization (WHO), volatile organic compounds are classified according to their boiling point or the resulting volatility:
description | Boiling range |
---|---|
1. Very Volatile Organic Compound (VVOC) | <0 to 50 ... 100 ° C |
2. Volatile Organic Compound (VOC) | 50 ... 100 to 240 ... 260 ° C |
3. Semi volatile organic compound (SVOC) | 240 ... 260 to 380 ... 400 ° C |
4. Organic compound associated with particulate matter or particulate organic matter (POM) |
380 ° C |
However, there is no uniform definition of what a VOC actually is (see Table 2). Some definitions actually contain information on vapor pressure, others, usually newer definitions, define VOCs via their photochemical reactivity as so-called precursor substances for the formation of ground-level ozone . In addition, certain organic substances are explicitly excluded from the VOC definition in some definitions. Another definition is common for assessing indoor air. This also applies to the emission of VOCs from products into indoor air
country | definition | source |
---|---|---|
- | All organic compounds (substances consisting primarily of carbon and hydrogen) with boiling points in the range from 50 to 260 ° C, with the exception of pesticides | World Health Organization (WHO), quoted from: Total Volatile Organic Compounds fact sheet (NPI, Australia) |
Australia | Any chemical compound made up of carbon rings or chains (and containing hydrogen) with a vapor pressure greater than 2 mm Hg (0.27 kPa) at 25 ° C, excluding methane. These compounds can also contain oxygen, nitrogen and other elements. Carbon dioxide, carbon monoxide, carbonic acid, carbonates, metal carbides and methane are explicitly excluded | NPI definition for volatile organic compounds |
Switzerland | Organic compounds with a vapor pressure of at least 0.1 mbar at 20 ° C or with a boiling point of at most 240 ° C at 1013.25 mbar | Ordinance on the incentive tax on volatile organic compounds (VOCV) of November 12, 1997 (as of October 8, 2002) |
Europe, Germany | An organic compound that has a vapor pressure of 0.01 kilopascals or more at 293.15 Kelvin or has a corresponding volatility under the respective conditions of use | Directive 1999/13 / EC ... of March 11, 1999 on the limitation of emissions of volatile organic compounds ... |
Europe | Any organic compound resulting from human activity, with the exception of methane, which can produce photochemical oxidants by reacting with nitrogen oxides in the presence of sunlight | Directive 2001/81 / EC ... on national emission ceilings for certain air pollutants (23 October 2001) |
Europe | Organic compound with an initial boiling point not exceeding 250 ° C at a standard pressure of 101.3 kPa | Directive 2004/42 / EC ... of April 21, 2004 on the limitation of emissions of volatile organic compounds due to the use of organic solvents in certain paints and varnishes ... |
Europe | Organic compounds of anthropogenic or biogenic origin with the exception of methane, which can produce photochemical oxidants by reacting with nitrogen oxides in the presence of sunlight | Directive 2008/50 / EC … of May 21, 2008 on air quality and cleaner air for Europe |
Europe | Chemical compounds based on carbon that are released into the air through natural sources or human activities (e.g. use of solvents, paints and varnishes, storage of fuels and their use at gas stations, automobile exhaust fumes) | Thematic strategy for air pollution control (as of December 1, 2005) |
United States | Any chemical compound based on carbon, with the exception of carbon monoxide, carbon dioxide, carbonic acid, metal carbides or carbonates, and ammonium carbonate, which are involved in photochemical reactions in the atmosphere | Code of Federal Regulation (CFR) 40, Part 51.100 (s), US EPA |
ISO, VDI | Any organic chemical compound that can be measured as follows: adsorption from air on Tenax TA, thermal desorption, gas chromatographic separation using a 100% non-polar column (dimethylpolysiloxane). VOC (volatile organic compounds) are all substances that appear between and including n-hexane and n-hexadecane in the gas chromatogram. Substances that appear earlier are classified as VVOCs (very volatile organic compounds) and substances that appear later are classified as SVOCs (semi-volatile organic compounds). | DIN EN ISO 16000-6, DIN EN ISO 13999-2, VDI 4300-6, AgBB evaluation scheme, DIBt approval principles, GEV test method for the EMICODE |
Accordingly, information on the emission of VOCs can only be assessed if the definition used is also given in addition to the information.
Microbial volatile organic compounds
As volatile organic compounds Microbial ( English Microbial Volatile Organic Compounds - MVOCs ) are volatile metabolic products described by microorganisms and fungi, of which were identified more than 200 compounds. Some of them are responsible for the musty smell of moldy paper or wood. One of these compounds that can be smelled intensely ( i.e. perceptible with a low odor threshold ) is 2,4,6-trichloroanisole .
swell
VOCs are emitted into the environment by a variety of anthropogenic and biogenic processes . Plants , animals , soils and seas are natural sources; The industrial use of solvents and traffic (see HC emissions ) are among the most important anthropogenic sources.
Natural sources
All living things (people, animals, plants, microorganisms) emit organic compounds into the environment. Swamps and ruminants are important natural sources of methane. Among the natural (non-methane) VOCs, the terpenes emitted by many plants dominate , including isoprene in particular . Bacteria and molds are to be mentioned among the natural sources polluting the indoor air, one speaks of MVOC (Microbial Volatile Organic Compounds), which can occur even after the organisms have died.
Anthropogenic sources
The use of solvents, halogenated hydrocarbons as refrigerants and road traffic dominate the man-made release of volatile organic compounds . If one considers the methane emissions from wet rice cultivation and cattle farming as an anthropogenic source of VOCs, this also results in a significant source.
In addition to the VOCs in the atmosphere, volatile organic substances are also found in indoor air and groundwater . Sources for these VOCs include a. Plastics , building materials, furniture and carpets , cleaning agents, and the consumption of tobacco products.
Health effects
Exposure to volatile organic compounds in indoor air can cause people to develop certain symptoms. Most commonly affected are people who are particularly sensitive to volatile chemicals because of a certain illness, for example. Symptoms such as headache, hypersensitivity reactions, tiredness, decreased performance, sleep disorders and irritation of the respiratory tract are summarized under the term " sick building syndrome ". The clinical picture is not defined in an internationally binding manner by the WHO. There is no generally accepted description of the clinical picture, so there is no ICD -10 code.
Effects on the nervous system are also known.
Emissions in the vehicle industry
In the vehicle industry, too, there are limit values for emissions of hydrocarbons, which are generally referred to as HC emissions .
Web links
- Text of the regulation on the limitation of emissions of volatile organic compounds when using organic solvents in certain plants
- Testing of VOC emissions in indoor air
- Announcement of the Federal Environment Agency: Comparative values for volatile organic compounds (VOC and aldehydes) in the indoor air of households in Germany, Bundesgesundheitsbl - Gesundheitsforsch - Gesundheitsschutz 2008, 51: 109–112, doi : 10.1007 / s00103-008-0425-9 . (Excerpt can be found under: look inside)
- VOCs as warning signals in the plant kingdom
- VOC directive in paints and varnishes / EU Decopaint directive
- CA Erdmann, KC Steiner, MG Apte: Indoor carbon dioxide concentrations and sick building syndrome symptoms in the base study revisited: analyzes of the 100 building data set (PDF; 242 kB), 2002, Proceedings: Indoor Air 2002
- Indoor pollution and sick building syndrome (PDF; 1.4 MB), Saarland University
Individual evidence
- ↑ World Health Organization (WHO), quoted from: Total Volatile Organic Compounds fact sheet (NPI, Australia).
- ↑ NPI Volatile Organic Compound definition and information ( Memento of March 24, 2012 in the Internet Archive ) (PDF; 90 kB), September 2009.
- ↑ Ordinance on the incentive tax on volatile organic compounds (VOCV) of November 12, 1997 (as of October 8, 2002) (PDF; 223 kB).
- ↑ Directive 99/13 / EC ... of March 11, 1999 on the limitation of emissions of volatile organic compounds ...
- ↑ 31st BImschV (of August 21, 2001), § 2, Paragraph 11
- ↑ Directive 2001/81 / EC ... on national emission ceilings for certain air pollutants
- ↑ Directive 2004/42 / EC… of April 21, 2004 on the limitation of emissions of volatile organic compounds due to the use of organic solvents in certain paints and varnishes and in vehicle refinishing products… .
- ↑ Directive 2008/50 / EC of the European Parliament and of the Council of May 21, 2008 on ambient air quality and cleaner air for Europe
- ^ Thematic strategy for air pollution control , as of December 1, 2005.
- ↑ Code of Federal Regulation (CFR) 40, Part 51.100 (s), US EPA (PDF; 22 kB).
- ↑ DIN EN ISO 16000-6, DIN EN ISO 13999-2, VDI 4300-6, AgBB evaluation scheme, DIBt approval principles, GEV test method for the EMICODE ( Memento of the original from May 30, 2012 in the Internet Archive ) Info: Der Archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. .
- ↑ Anne Korpi, Jill Järnberg, Anna-Liisa Pasanen: Microbial volatile organic compounds . In: Critical Reviews in Toxicology . tape 39 , no. 2 , 2009, p. 139-193 , doi : 10.1080 / 10408440802291497 , PMID 19204852 (English).
- ↑ Federal Office for the Environment : Volatile organic compounds in groundwater In: bafu. admin.ch , accessed on September 16, 2018.
- ↑ Pollutants in construction - background information ; Retrieved February 21, 2013.
- ↑ Organic solvents (polyneuropathy, encephalopathy) . berufskrankheit.de. Retrieved January 8, 2020.