GLOSSARY

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Aflatoxins: Highly toxic (ten times more toxic than the Seveso dioxin!) and carcinogenic materials, produced by the common housemould on bread, pinda's, etc...
Ah-receptor: or aromatic hydrocarbon receptor in the living cells can be functionally compared with a keylock. Aromatic compounds, such as dioxins and polycyclic aromatic hydrocarbons (PAH's), can fit like a key in the lock. Above a certain amount of occupied locks, a mechanism in the cell is started which makes enzymes to breakdown these unwanted chemicals in the body, but that mechanism can also introduce unwanted side reactions like supression of the immune system and the breakdown of vital aromatic molecules like vitamin K.
BaP: Benzo-a-pyrene, the most toxic, mutagenic and cancerogenic PAH member. The 16 most toxic PAH's are referenced to BaP with TEF (toxicity equivalent) factors. The sum of this gives an impression of the total toxicity.
AOX: Absorbable organic halogens. This is a method for the measurement of chlorinated, brominated, jodinated and/or fluorinated organic material in water. For that purpose, waste or river water is conducted trough active carbon. The active carbon absorbs organic material and is incinerated afterwards. The amount of chlorine, bromine, jodine and/or fluorine is then measured. The AOX just tells about amounts, not about toxicity. Even in rivers far from any pollution a relatively high AOX is measured, as natural chlorinated phenolics and humic acids are formed by wood rotting fungi.
BBP: butylbenzylphthalate, is a phthalate made by the reaction of butylalcohol and benzylalcohol with phtalic acid. Has a medium boiling point and medium volatility. This phthalate is mainly used in printing inks on polyolefines like PE and PP.
CMC: Carboxy methyl cellulose, is made from pure cellulose which is etherified with methylalcohol. This gives it extraordinary water absorbing properties. The material can hold up to 400 times it own weight of water.
CFC's: Chlorine fluorine carbons, formerly used in hughe quantities as coolant and propellant in spray cans. Because they were not easely degaded in the atmosphere, they could reach the higher stratosphere, were stronger UV-light split off chlorine, which depleted part of the ozone layer.
DBP: dibutylphthalate, is a phthalate made by the reaction of n-butylalcohol and phtalic acid. Has a low boiling point and relative high volatility. This phthalate is mainly used in printing inks. It occurs naturally in the odour components of lovage and selery.
DCE: 1,2 dichloroethane is the intermediate for making PVC. It is made by direct chlorination of ethylene or by oxychlorination, where a mix of hydrochloric acid, oxygen/air and ethylene is transformed to DCE and water by a copper catalyst. The hydrochloric acid may come from the cracking of DCE to form VCM, or from external processes, or from the incineration of chlorinated wastes. Other industrial used reactions to make DCE also exist or are developed. DCE is also used as raw material for the production of amines.
DEHP: di-ethylhexylphthalate, sometimes also called DOP (di-octylphthalate), is a phthalate made by the reaction of ethylhexylalcohol and phtalic acid. It is an oily product with a high boiling point, low volatility and low solubility in water. It can readily be mixed with PVC, where it softens the normally hard material. PVC plasticised with DEHP is the only flexible material approved by the European Pharmocopoeia for use in blood and plasma transfusion equipment.
DIDP: di-isodecylphthalate, is a phthalate made by the reaction of isodecylalcohol and phtalic acid. Has a slightly higher boiling point and lower volatility than DINP. Is seldom used.
DINP: di-isononylphthalate, is a phthalate made by the reaction of isononylalcohol and phtalic acid. Has a slightly higher boiling point and lower volatility than DEHP. Mainly used to make soft toys from PVC.
Dioxins: See PCDD/F.
EDC: Ethylene dichloride, or more accurate 1,2 dichloroethane, see DCE.
Endometriosis: A painfull desease which gives chronic inflammations of mucous membrane, growing outside of the uterus of female animals and women.
Ethylene/propylene: is made by cracking of LPG or naphta, this gives resp. a 90% or 70% yield of ethylene and propylene. The remainders are benzene, butadiene, light fractions and PAH's. Benzene and butadiene are used for other purposes, the light fractions are mixed with petrol and the PAH's are incinerated. Ethylene has many applications, mainly to make different plastics.
gram: The different subdivisions of weight are as follows:

1 ton = 1.000.000 g (1 Mg or megagram)
1 kg  =     1,000 g (kilogram)
1 g   =         1 g (gram)
1 mg  =         0.001 g (milligram)
1 µg  =         0.000001 g (microgram, also abbreviated to ug or mcg)
1 ng  =         0.000000001 g (nanogram)
1 pg  =         0.000000000001 g (picogram)
1 fg  =         0.000000000000001 g (fentogram)
Fingerprint: Each chemical reaction where dioxins are formed or any incineration of synthetic or natural (always) chlorine containing materials gives its typical mixture of the different dioxins, called congeners. In that way it is more or less possible to trace back the origin of a dioxin contamination.
HCB: Hexachlorobenzene, mainly a byproduct from combustion when traces of chlorine are present like in the use of fuel at sealevel. It resists biodegradation and can accumulate in the food chain.
HCFC's: Hydrogen chlorine fluorine carbons, used as replacement for CFC's. Because of the presence of a hydrogen atom, the HCFC's are much faster degraded than CFC's. That means that a much smaller part is reaching the ozone layer. Replacement of CFC's by HCFC's and other materials already reduced the global ozone depletion potential to 3% of what it was in the early nineties.
HDPE: High density polyethylene. The polymerisation process from ethylene is under low pressure, but with a organo-metallic catalyst. Because this type of polymerisation gives less side chains, the endproduct has a higher density and a higher stiffness. It is mainly used for all kinds of containers and pipes.
Laminate: Packaging composed of layers of different materials, to reach properties not possible by one material alone. E.g. brick packaging is a laminate of PE, aluminium and cardboard. PE offers chemical inertness, aluminium makes it 100% light- and vaporthight and cardboard gives it the stiffness and printability.
LCA: Life Cycle Analyses is a scientific method to investigate the impact of a material - or a method - on the environment during its whole life, in a certain application, from the use of raw materials and energy until the deposit after use. In that way the environmental impact of different materials (e.g. PVC, PET and glass) or different methods (e.g. one-way and return) for the same purpose (e.g. mineral water packaging) can be compared.
LDPE: Low density polyethylene. The polymerisation process from ethylene is under very high pressure (thousands of bars) with a little oxygen as catalyst. Because this type of polymerisation gives a lot of side chains, the endproduct has a low density. It is mainly used as sheets in packaging.
LLDPE: Linear low density polyethylene. The polymerisation process from ethylene is under low pressure, but with a organo-metallic catalyst. This type of polyethylene has less side chains, which makes it less vulnarable to oxydation and attack of UV-light. The molecular weight is kept lower than for HDPE and also other monomers which makes side chains are introduced to lower the density. It has mainly the same purposes as LDPE.
MTD: Maximum tolerated dose, is the maximum of any product that can be given to an animal, without killing it in a limited time. Many tests for carcinogenity use the MTD, half the MTD, a quarter of the MTD and no product, to do life time tests of animals to check for carcinogenity of a product. A real carcinogen developes excess cancers at the MTD and half that amount at half the MTD. etc... In fact at the MTD, the animal is continuously poisoned, that can result in a lot of excess cancers, caused by the poisoning, not the carcinogenity of the product. In such cases, lower doses give much lower cancer rates and at a certain level, no excess cancers are seen anymore. See the papers of Bruce N. Ames: "Too many rodent carcinogens" (not a popular scientific chat!).
PAH's: Polycyclic aromatic hydrocarbons are naturally present in crude petroleum and are formed by any incomplete combustion. A few microgram per liter seawater is enough to give problems in the growth of plankton. Several members are highly potent carcinogens. Even in fires where PVC or other chlorinated stuff was involved, the amounts of PAH's are much more significant both in quantity (in the thenthousands) and toxicity (in the hundreds of times more potent). See dioxins and PAH emissions compared. They are persistent and liable to accumulate in the food chain.
nitro-PAH's: These are nitrated variants of the PAH's. Until now the most potent carcinogens and mutagens found. They are mainly products of combustion.
PC: Polycarbonate. The raw materials here are chlorinated compounds: phosgene and some chlorinated aromatic compounds. The aromatic compounds come from crude oil, the chlorine and sodiumhydroxyde from salt. The polymerisation is by splitting off chlorine by means of sodiumhydroxyde. The endproduct contains no chlorine anymore. PC has a very high temperature and impact resistence and has many applications, from CD's to airplane windows and temperature resistent kitchen utensils.
PCB's: Polychlorinated biphenils. A class of industrial products used as insulating and heating oil and as a hydraulic fluid. In the seventies and eighties it was discovered that PCB's could harm the reproduction of seals and other wildlife. The production of PCB's is already stopped more than ten years ago. Remaining PCB's from e.g. transformers are burned or transformed in special equipment in an environmentaly sound way.
PCDD/F: Polychlorinated p-dibenzo dioxins and polychlorinated p-dibenzo furans, or shortly called 'dioxins' are a family of 210 different unwanted by-products of mainly combustion of any organic material, whether it is chlorine containing or not. They also can be created in certain chemical processes. See also I-TEQ.
PCP: Pentachlorophenol, a pesticide used for wood and textile protection, works against fungi, bacteria and worms. Was contaminated with relatively much dioxins in the earlier days. Now forbidden in several countries.
PE: For pipes and containers, normally HDPE, high density polyethylene is used. For packaging, mostly LDPE, low density polyethylene is used, because it is more flexible.
Peer review: is a review of any scientific work by independent scientists, mainly to look if there are not made methodologic errors. Normally they don't give comment on the produced figures themselves, except for clear mistakes.
PET: Polyethylene terephthalate. Is made from terephthalic acid and ethylene glycol, both derived from crude oil. The production involves many steps, therefore the energy use is higher than for many other plastics. It has a high tensile strength, which makes it suitable to make fibers ('polyester') and pressurised bottles for carbonated water and soft drinks.
PE-X: Polyethylene, crosslinked with some other mononers to augment the strength and reduce the impact of oxydation.
Phthalates: A group of chemicals made by the reaction of alcohols with phthalic acid. This kind of chemicals are called esters, or in this case phthalic esters or shortly phthalates. Phthalates among others can be mixed with PVC, to make it flexible. They are also used in printing inks and glues and rubber. Depending of the type of alcohol, used to make the ester, different properties are obtained for different applications. A rather high volatility is the result, if short-chained alcohols are used like in dibutylphthalate (mainly used in printing inks, but also found in the odour components of lovage and selery), while the phthalates used in PVC mainly have a low volatility. The bulk of phthalates, used in soft PVC are DEHP (di-ethylhexylphthalate) and DINP (di-isononylphthalate).
POP's: Persistent Organic Polutants. These are materials that are not readily broken down, either by bacteria, fungi and/or UV-light, oxydation, etc... They also cause some harm to ecosystems. Examples of POP's are dioxins, PCB's, PAH's and nitro-PAH's. In many cases these are products of incomplete combustion of all kinds of incineration.
PP: Polypropylene. The polymerisation process from propylene is under low pressure, but with an organo-metallic catalyst. The polymerisation process results in about 6% of an unsuitable byproduct which is extracted and incinerated. It has a very high resistence against tear up and has a high tensile strength, which makes is suitable to make cables and containers.
PS: Polystyrene. The raw materials here are benzene and ethylene, which makes via ethylbenzene the monomer styrene. The polymerisation process is mainly in bulk with peroxydes as catalysts. Used in many kitchen utensils and as expanded polystyrenefoam (EPS) for insulation. These foams are made by injecting air in the molten mass, not by CFK's.
PU: Polyurethane. The raw materials here are a chlorinated compound: phosgene and some nitrated compounds. The nitrated compounds come from crude oil and nitrogen, the chlorine from salt. The building block is made by splitting off hydrochloric acid. The endproduct is made by mixing two compounds and at the same time some foaming agent can be mixed. This gives the foam used for matrasses and seats in cars and airplanes. The endproduct contains no chlorine anymore. The hydrochloric acid split off during the process is used again to make VCM/PVC.
PVC: Polyvinyl chloride, a plastic composed of 43% of oil products and 57% of salt as raw material. Therefore it uses less exhaustible raw materials and less energy than any other plastic or many 'classic' materials. This makes it excellent for sustainable development. PVC has an extremely wide range af applications, from toys via (waste) water lines to bloodbags.
PVDC: Polyvinylidenechloride, a plastic composed of more chlorine of salt as raw material than PVC. This gives it very good barrier properties for flavours and aroma's. It is mainly used as special packaging for foodstuffs.
TDI: Tolerated daily intake, is the amount of a product that may be ingested daily from all sources (but mainly food) that will not have adverse effects (or acceptable effects), even over a total lifetime. In general, that is based on animal assays, where the limit is based on the lowest level of what gives no observed adverse effect (the NOAEL) of the most vulnarable animal. For humans, a additional safety factor of 100 is applied to set the TDI. For real carcinogens, the TDI is based on a calculation, derived from the number of excess cancers that animals had, where less than 1 excess case on 1 million animals should occur. Again a safety factor of 100 is applied.
I-TEQ: International toxicity equivalents. From the total 210 different (poly)chlorinated dioxins and -furans, called congeners, only seventeen are (very) toxic. Between these seventeen, there are differences up to a thousand times in toxicity. To make any comparison possible, the amounts of the seventeen toxic chlorinated dioxins/furans are multiplied with a toxicity factor (I-TEF) and added together. The toxicity factor compares the toxicity of a congener with the most toxic dioxin, which escaped in Seveso.
TOC: Total organic carbon. The amount of dissolved organic material in rivers, drinking water, test solutions, waste water, etc., can be determined and is expressed in carbon content of the sample. That doesn't say anything about the toxicity of the organic material found.
Thyroxine: A hormone produced by the thyroid gland. It is involved in the motoric and mental development of young children.
In utero: In utero means in the mother's womb. The growing child in this period is especially vulnerable to hormone disrupting chemicals that can pass the blood barrier of the placenta.
VCM: Vinyl chloride monomer, is the basic material of which PVC is made by polymerisation. In general, VCM is made by a reaction between chlorine or HCl (hydrochloric acid) and ethylene, which forms DCE (1,2 dichloroethane). That is cracked at high temperature, where VCM and HCl are formed. The latter is reused in the process. VCM is a known human carcinogen, for which low limits are imposed at the workplace.

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Created: September 13, 1997.
Last update: September 28, 1999.

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