The presence of artificial substances in the environment is measured in parts per million (ppm) or parts per billion (ppb)
 

1ppm = 1mg/kg = (1 divided by 1000) g por kg
 

The accumulation of artificial substances in the environment apenes in two different ways:

• Sedimentation
• Concentration and Evaporation

Bioaccumulation
 

Bioaccumulation occurs when an organism ingests more quantity of a substance than it is digesting. Biaccumulation reaches higher values with each step in the trophical chaín. Originally, unmeasurable small concentrations of contaminants can therefore accumulate to levels millions of times higher in concentration within the species of wild fauna or within the human body.
 

PCB concentration in North Sea sediment for example is 5000 times higher (0.01 ppm) than in the North Sea water (0.000002 ppm). PCB concentration in the bodies of marine mammals in the North Sea (160 ppm) is 1000 million times higher than in the water.
 

The level of bioaccumulation within the body of living organisms varies in different body tissues. The graphic below shows the different levels of bioaccumulation of the pesticida Atrazin in the water, as well as in different organs of the fish species Coregonus fera.

In general terms, toxic substances are accumulated principally in digestive organs: liver and kidneys. But different substances do accumulate in different organs:

• Chlorine based compounds: Fat and brain tissue
• Lead and fluoride: Hair, teeth, bones
• Other substances: Muscle tissues

Example for the consequences of toxic bioaccumulation: the Beluga whales of the Sankt Lorenz current

A total of 20 different toxic substances has been found accumulated in Beluga whales. For example, up to 1.725 mg PCB / kg. The milk of female whales contains 3,400 times more PCB than the maximum level of PCB permitted for bottled water in the US.
 

This resulted in th following diseases encountered in Beluga Whales:

• Gastric ulcers
• Pnuemonia Peritonitis
• Chronic Hepatitis
• Virus
• Holes in pulmonary veins
• Skin diseases
• Cancer of the liver, stomach and the mamary glands
• Illnesses similar to AIDS.

Other examples for bioaccumulation of toxins

• Sea lions in California: Drastic increase of abortions, Mothers that did abort did count with PVCB levels being eight times higher than in mother with healthy pubs. Direct cause of death were bacterias that reproduce within sick mothers.
• Equally, the seals of the Baltic Sea and the ones off the coast of the Netherlands suffer high rates of abortion.
• In the bodies of porpoises levels of PCB have been found to be 70,000 times higher than in sea water.
   

Persisitence of toxic substances – There are three levels of persistence:

1. Not persistent: organic compounds: sewage, feces, etc.; Nutrients: nitrogene and phosphate y fosfatos (sewage and agriculture)
2. Highly persistent: organic compounds, chemicals containing fluoride and chlorine
3. Do not decompose at all: Unorganic substances: salts, acids, heavy metals, asbest

Many times the metabolized products of toxic substances are even more toxic than the original substances. Example: Metabolites of DDT = DDD + DDE

Levels of concentration of toxic substances in living organisms:

• NOEL – “NO Effect Level” = level without any measurable effects.
• LOEL – “Lowest Observed Efect Level” = Level that results in the minimum effects being statistically measurable.
• Sublethal = The negative effects of the toxic substance in the organism are not lethal.
• LD 10 = 10% of the organisms die
• LD 50 = 50% of the organisms die

“Stop the Poison” Campaign
Dioxins and Furans
Stop Garbage Burning
Marine dead zones and algae blooming
Dead zone: Bay of Paracas
Dead Zone: Bay of Chimbote
“Clean-up Peru” Campaign