Plants and mushrooms accumulate the Chernobyl radionuclides at a level that depends upon the soil, the climate, the particular biosphere, the season, spotty radioactive contamination, and the particular species and populations (subspecies, cultivars), etc. Each radionuclide has its own accumulation characteristics (e. g., levels of accumulation for Sr-90 are much higher than for Cs-137, and a thousand times less than that for Ce-144). Coefficients of accumulation and transition ratios vary so much in time and space that it is difficult, if not impossible, to predict the actual levels of Cs-137, Sr-90, Pu-238, Pu-239, Pu-240, and Am-241 at each place and time and for each individual plant or fungus. Chernobyl irradiation has caused structural anomalies and tumorlike changes in many plant species. Unique pathologic complexes are seen in the Chernobyl zone, such as a high percentage of anomalous pollen grains and spores. Chernobyl's irradiation has led to genetic disorders, sometimes continuing for many years, and it appears that it has awakened genes that have been silent over a long evolutionary time.

Problems complicating a full assessment of the effects from Chernobyl included official secrecy and falsification of medical records by the USSR for the first 3.5 years after the catastrophe and the lack of reliable medical statistics in Ukraine, Belarus, and Russia. Official data concerning the thousands of cleanup workers (Chernobyl liquidators) who worked to control the emissions are especially difficult to reconstruct. Using criteria demanded by the International Atomic Energy Agency (IAEA), the World Health Organization (WHO), and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) resulted in marked underestimates of the number of fatalities and the extent and degree of sickness among those exposed to radioactive fallout from Chernobyl. Data on exposures were absent or grossly inadequate, while mounting indications of adverse effects became more and more apparent. Using objective information collected by scientists in the affected areas--comparisons of morbidity and mortality in territories characterized by identical physiography, demography, and economy, which differed only in the levels and spectra of radioactive contamination--revealed significant abnormalities associated with irradiation, unrelated to age or sex (e.g., stable chromosomal aberrations), as well as other genetic and nongenetic pathologies.

More than 50% of Chernobyl's radionuclides were dispersed outside of Belarus, Ukraine, and European Russia and caused fallout as far away as North America. In 1986 nearly 400 million people lived in areas radioactively contaminated at a level higher than 4 kBq/m(2) and nearly 5 million individuals are still being exposed to dangerous contamination. The increase in morbidity, premature aging, and mutations is seen in all the contaminated territories that have been studied. The increase in the rates of total mortality for the first 17 years in European Russia was up to 3.75% and in Ukraine it was up to 4.0%. Levels of internal irradiation are increasing owing to plants absorbing and recycling Cs-137, Sr-90, Pu, and Am. During recent years, where internal levels of Cs-137 have exceeded 1 mSv/year, which is considered "safe," it must be lowered to 50 Bq/kg in children and to 75 Bq/kg in adults. Useful practices to accomplish this include applying mineral fertilizers on agricultural lands, K and organosoluble lignin on forestlands, and regular individual consumption of natural pectin enterosorbents. Extensive international help is needed to provide radiation protection for children, especially in Belarus, where over the next 25 to 30 years radionuclides will continue to contaminate plants through the root layers in the soil. Irradiated populations of plants and animals exhibit a variety of morphological deformities and have significantly higher levels of mutations that were rare prior to 1986. The Chernobyl zone is a "black hole": some species may persist there only via immigration from uncontaminated areas.

More than 50% of Chernobyl's radionuclides were dispersed outside of Belarus, Ukraine, and European Russia and caused fallout as far away as North America. In 1986 nearly 400 million people lived in areas radioactively contaminated at a level higher than 4 kBq/m(2) and nearly 5 million individuals are still being exposed to dangerous contamination. The increase in morbidity, premature aging, and mutations is seen in all the contaminated territories that have been studied. The increase in the rates of total mortality for the first 17 years in European Russia was up to 3.75% and in Ukraine it was up to 4.0%. Levels of internal irradiation are increasing owing to plants absorbing and recycling Cs-137, Sr-90, Pu, and Am. During recent years, where internal levels of Cs-137 have exceeded 1 mSv/year, which is considered "safe," it must be lowered to 50 Bq/kg in children and to 75 Bq/kg in adults. Useful practices to accomplish this include applying mineral fertilizers on agricultural lands, K and organosoluble lignin on forestlands, and regular individual consumption of natural pectin enterosorbents. Extensive international help is needed to provide radiation protection for children, especially in Belarus, where over the next 25 to 30 years radionuclides will continue to contaminate plants through the root layers in the soil. Irradiated populations of plants and animals exhibit a variety of morphological deformities and have significantly higher levels of mutations that were rare prior to 1986. The Chernobyl zone is a "black hole": some species may persist there only via immigration from uncontaminated areas.

Radioactive contamination from the Chernobyl meltdown spread over 40% of Europe (including Austria, Finland, Sweden, Norway, Switzerland, Romania, Great Britain, Germany, Italy, France, Greece, Iceland, Slovenia) and wide territories in Asia (including Turkey, Georgia, Armenia, Emirates, China), northern Africa, and North America. Nearly 400 million people resided in territories that were contaminated with radioactivity at a level higher than 4 kBq/m(2) (0.11 Ci/km(2)) from April to July 1986. Nearly 5 million people (including, more than 1 million children) still live with dangerous levels of radioactive contamination in Belarus, Ukraine, and European Russia. Claims that the Chernobyl radioactive fallout adds "only 2%" to the global radioactive background overshadows the fact that many affected territories had previously dangerously high levels of radiation. Even if the current level is low, there was high irradiation in the first days and weeks after the Chernobyl catastrophe. There is no reasonable explanation for the fact that the International Atomic Energy Agency and the World Health Organization (Chernobyl Forum, 2005) have completely neglected the consequences of radioactive contamination in other countries, which received more than 50% of the Chernobyl radionuclides, and addressed concerns only in Belarus, Ukraine, and European Russia.