Chemical formation
Dioxines are formed between 2 benzene rings, with one or two O-atoms and a Cl-atom. The connection between the 2 benzene rings are with the O-atom.

• Connection with 1 O-atom: PCDF (polychloredibenzofurane)
• Connection with 2 O-atoms: PCDD (polychloredibenzodioxines)

If the temperature is high enough, min. 850 C, the the dioxines are “broken”-burned. But dioxines may again be generated in the stack when the flue gasses have again 200-400 C.

Pollution source
Dioxines and furanes are mainly generated by heat systems and open fires. Dioxines are also created by waste incineration, the non-ferro industry and by domestic heat systems (espacially wood furnace). The dioxines arrive in the human body mainly by the food chain. Mosly: fat fish, milk, fat of meat, product with animal fat like sauses, cakes and desserts.

Most important health effects
Dioxines are causing cancer, may have an effect on the gown and development of the human body. The may disturb the functioning of hormones and the immunity system of the human body.

Human biomonitoring results (table 1) in different geographical area’s of environmental assessment (in Belgium) shows people have always a certain level of dioxines and furanes in there body. There is no significant different level in different area’s of environmental assessment.

Some adviced values for secure levels
There is no adviced value for secure levels. If the concentration of dioxines in the human body is low, the lower the change on cancer and the better.

Chemical formation
Formation PCB’s are formed by the chemical reaction of a free Cl-atom with benzeen rings. The temperature need to be between 250 °C and 400 °C.

Pollution sources
PCB's have 209 chemical derivations. PCB138, PCB153, PCB180 are the most frequent. PCB's where produced and used by the industry, due to there thermical excellent character. For example in transfo's of refrigerators. Today they may not be produced and used anymore. But they are still in our environment due to leakages and incineration of those PCB containing machines. PCB's are accumulating in fat of fish, fat of meat, milk, etc.

Most important health effects
PCB's may cause a lower weight of natal babies, disturb the functioning of the thyroid gland and may cause a slow development of intelligents. PCB's may disturb the functioning of hormones and the immunity system of the human body.

Pollution sources
One of the most important pollution sources of cadmium is cigarette smoke. In the past mostly non-ferro industry and incinerators where emissioning cadmium. Also some construction materials where containing cadmium. Today cadmium is present in salads, spinage and seldom. Also in meat of animals which are living in polluted area's.

Food and cigarette smoke are the largest potential sources of cadmium exposure for members of the general population. The average person ingests about 30 micrograms (ug) of cadmium from food each day. Smokers absorb an additional 1 to 3 ug per day from cigarettes. Average cadmium levels in cigarettes range from 1,000 to 3,000 ppb.

Most imporatant health effects
During the pregnancy cadmium may disturb the functioning of the placenta. This may have cause that the baby is lighter and this is why babies of smoking mothers are mostly lighter. Cadmium may disturb the functioning of the kidneys, disturb bone production and causes cancer.

Some adviced values for secure levels
For cadmium in blood is a value of 5 µg/L not harmfull For cadmium in urine is a value of 2 µg/g creatinine not harmfull. Persons who smoke one or more packs of cigarettes per day blood Cd concentrations ar 2 ug/l, tenfold over those of nonsmokers about 0.2 ug/l.

Note: smokers have significant higher concentrations of Cadmium in there body/blood

Pollution sources
In the past mainly, non ferro industry, cars with lead containing fuel, lead tubes for drinking water and lead painting liquid where the pollution sources. Today a lot of those sources don't exist anymore. But by continuous circulation of dust and water, lead stays in our environment.

Most important health effects
Exposure of lead before the birth or to young children may have a negative influence on the inteligent development, control of small movements or concentration capacity. By long exposure to low amounts the functioning of the kidney's and the feritilyment may be disturbed.

Some adviced values of secure levels
The WHO (World health organization) considers that the health is not in danger when the values are lower then 100 µg/L.

Note: smokers have significant higher concentrations of Lead in there body/blood

Pollution sources
In all combustion processes, there are small particulates generated, cars, industry, incinerators,... Particulates are tiny particles in the air that are classified by there size. PM10S have a diameter of less than 10 microns, PM2.5S less than 2.5 microns, and PM1S are ultrafine particulates (less than 1 micron). 

Most important health effects
The smaller the size of the particles, the more dangerous the health effects. The smaller the particles, the less they are filtered out. Their miniscule size allows them to be breathed deeply into the lungs and to be absorbed directly into the blood stream where they can persist for hours. Particulates can travel through the cell walls and into the cell nucleus affecting the cell's DNA. Fine particulates have been associated with both respiratory and cardiovascular disease and with lung cancer. 

Some adviced values of secure levels
The WHO (World health organization) considers that a reduced life expectancy of 40 days per person over 15 year for about 1 mcg/m3 in the air for PM2.5.

Pollution sources
In all combustion processes. 

Most important health effects
Emission of CO & CO2 is leading to global warming. The increase in CO2 leads to melting of polar ice caps which increases the sea level and pose danger for the people living near coastal areas.

Some advices for humans:
The world need to cut less trees.

Pollution sources :
industry, also incinerators because in almost all type of waste there is Cl and S present. So, combustion in presents of S or Cl. The acids, are creating "acid rain".

Most important health effects :
Acid rain has no direct effect on human health. You can walk in "acid rain", or swim in a "acid rain pond". 

Some adviced values of secure levels
The critical level for SO2 is 30 µg/m3 measured as an annual average.

Pollution sources
In all combustion processes. NOx is produced from the reaction of nitrogen and oxygen gases in the air during combustion, especially at high temperatures, NOx is generated very well above 1200 - 1300 degr.C. 

Most important health effects
NOx has direct and indirect effects on human health. It can cause breathing problems, headaches, chronically reduced lung function, eye irritation, loss of appetite and corroded teeth. Indirectly, it can affect humans by damaging the ecosystem.

Some adviced values of secure levels
The critical level for NOx is 30 µg/m3 measured as an annual average.