Global Trends: The Environment:

Globalization & Persistent Toxic Substances

by Ott Roots, Ph.D
Estonian Environmental Research Centre

The Earth is a complex system of subtle
interrelationships among the air, water,
soil, animals, plants and microbes –
a truly unique planet in our solar system.

“A Better Future for the Planet Earth “,
Japan, 2002

When “The Silent Spring” was published in the beginning of the 1960ies, the people still didn’t believe that the chemicals could seriously endanger the surrounding environment. However, the first cases of Yusho disease, caused by the polychlorinated biphenyls (PCBs), were detected at the end of the 1960ies in Japan and also during the 1970ies in Taiwan. Although the production of the compound had been commenced as early as in 1929, it was detected for the first time in nature in the course of an environmental monitoring at the end of the 1960ies. The 1990ies brought along yet another unpleasant surprise – namely, the problem of dioxins. Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) have never been produced internationally, but they are unwanted by-products of numerous chemical industrial processes and of all combustion processes.

Chemicals are nowadays produced and marketed in great numbers. About 400 million tons of chemicals are produced by the worldwide chemical industry each year. So far, the dangerous compounds have been found mainly as a result of chemical monitoring, carried out after the appearance of problems relating to human health. This approach has proven to be very costly. It would be much wiser to prevent the situation (by using the Integrated Pollution Prevention and Control System as well as the Best Available Technique), so that we wouldn’t have to waste valuable time and resources on the later monitoring and analysis of the compounds, as well as on the cleaning of polluted areas. The aim of this article is not to touch upon the preventive problems, but to present the hazards, which will follow if all the aspects of the implementation of environmental monitoring are not carefully considered.   

The monitoring program of persistent toxic substances (PTS) can never achieve the full extent of the geographical resolution to cover all the parts of the world. This is not only because of the cost of the analytical program, but also because of zoological and geographical reasons. Still, there is a need to obtain comparable results at least from the main sub-regions, but, because of the above-mentioned reasons, the sampling network has to be sparsely distributed. In my opinion, the regions could be designated on the basis of the recommendation made by UNEP Chemicals, in which the world is divided into 12 regions (Arctic; North America; Europe; Mediterranean; Sub-Saharan Africa; Indian Ocean; Central and North-East Asia; South-East and South Pacific; Pacific Islands; Central America and the Carribian; Eastern and Western South America and Antarctica). The regions are linked to important international waters [1].

In each of the regions, the work could be coordinated by a center consisting of 4-6 people. These centers would be financed by the countries belonging to the region through their respective Environmental Monitoring Funds. The countries belonging to each region would, in their turn, establish a work-group consisting of local experts, which would be in direct contact with the center of the region. Modern information technology facilitates fast exchange of information, including videoconferences. All this enables to streamline the monitoring process as well as to save money. At the same time, the purposeful implementation of the Fund would help to bridge the gap between the developed and the developing countries. The Fund could also give advice on the implementation of local monitoring, and it could be used for the timely ordering of control samples (e.g., the price of a single dioxin or furan analysis can exceed 1000 USD). But in addition to the above, expensive analytical equipment and highly trained personnel are needed. At these times of cross-border air pollution, when even the slightest contents of determined substances (for example, PTS) can be the cause of human health disorders, the level of national monitoring analyses must be comparable with the level of global monitoring analyses. Otherwise we will lose time and money. One could ask, whether the number of PCDD/Fs analyses done in a small country is sufficient to cover the huge costs of equipment and training, or whether it would be less expensive to order the analyses from abroad. Evidently, the regions should also select one or two laboratories, which would comply with the international requirements, so that the results of environmental monitoring could be used for comparison both at the global and regional level. The other possibility [2] would be to collect the samples in different countries using the same equipment and methods, or to analyze them in one laboratory in Europe, America, Asia, etc.

If the selection of regions and laboratories should be rather easy, then the selection of bio-indicators used in environmental monitoring could prove to be much more difficult. The integration of chemical and biological monitoring provides more comprehensive information for quality assessment, as well as more data on the ecological functioning of ecosystems. At this point, the advice given by the regional center would be of crucial importance, as it seems that the regions will have to select their bio-indicators in cooperation with local experts. Bio-indicators should comply with the following requirements:

They should be caught from all parts of the region (important for comparison);
They should be easy to collect;
They should be of suitable size for pre-analytical sample treatment;
Their biology should be fairly well known;
They should be important commercial species.

When studying the distribution and bio-accumulation of toxic compounds, one should also focus on supplementary data in order to avoid false conclusions. Findings on the deposition and concentrations of persistent toxic substances in air and precipitation [3] should be combined with studies on the atmospheric transport, seawater processes and cycling between water, plankton, fish, mollusks, algae, seals, etc [2]. For example, when analyzing the Baltic Sea fish organism [3], then besides the age of the fish also other characteristics such as the length, sex, weight, fat content, maturity, the percentage of empty stomachs (and the content of different food in stomachs) [4], etc., should be taken into account. The differences in hydrological features and the lack of information about fish migrations can make the situation in the Baltic Sea more complicated than in fresh water. 

Consequently, the prerequisite of successful environmental monitoring is the establishment and engagement of a broad group of experts, which would involve chemists, biologists, meteorologists, hydrologists, etc. In the next few years, the cooperation related to environmental monitoring should improve significantly, since the streamlining of the monitoring process should help to save valuable time and resources. 


1. Regionally Based Assessment of Persistent Toxic Substances – Global Report. 2003. UNEP Chemicals, Geneva, Switzerland, 211p. (

2. O. Roots. Toxic chlororganic compounds in the ecosystem of the Baltic Sea. Ministry of the Environment of Estonia, 1996. 144p. (ISBN-9985-9072-0-5).

3. C. Agrell, P. Larsson, L. Okla, G. Bremle, N. Johansson, M. Klavins, O. Roots, O. and A. Zelechowska. Atmospheric and River Input of PCBs, DDTs and HCHs to the Baltic Sea. In.: A System Analysis of the Baltic Sea (Eds. F. Wulff, L. Rahm and P. Larsson). Ecological Studies, (Springer Verlag), 2001, v. 148, pp. 149-175 (ISSN 0070-8356; ISBN 3-540-67769-0).

4. O. Roots. Did natural changes save the gray seal of the Baltic Sea? Hypothesis or reality. Toxicological and Environmental Chemistry (Gordon and Breach Science) (Germany)), 1999, v. 69, No. 1-2, pp. 119-131.


BWW Society Dr. Ott Roots currently serves at the Estonian Environment Research Centre. He was educated as a chemist-technologist at the Tallinn Technical University, and graduated in 1969; he received his Ph.D. in Organic Chemistry and Hydrobiology from the Institute of Chemistry, Estonian Academy of Sciences  in 1983. His scientific career includes service as Scientist, Institute of Zoology and Botany, Estonian Academy of Sciences (1971-74), Scientist, Institute of Thermo- and  Electrophysics, Department of the Baltic Sea, Estonian Academy of Sciences (1974-84), Chief researcher, Institute of Applied Geophysics, Baltic Branch (1984-90), Chief researcher, Tallinn Technical University, Water Protection Laboratory (1990-92), Senior Scientist, Institute of Experimental and Clinical Medicine, Department of Environmental Carcinogenesis (1992-93), Monitoring Councillor, Ministry of the Environment of Estonia Environment Information Centre (1993-2000), Councillor, Ministry of the Environment of Estonia, Department of Environmental Management and Technology (2000-02), and Monitoring Coordinator, Estonian Environment Research Centre (2002-present). His honors and awards include Second prize in the Tallinn Technical University students scientific works competition; Third prize in the Institute of Thermo- and Electrophysics, Estonian Academy of Sciences young scientist competition; Bronze medal from Environmental Protection Exhibition in Moscow (Russia); Ministry of the Environment of Estonia - Honour Certificate; Nominee of the Estonian Science Award (twice); Ministry of the Social Affairs of Estonia – Honour Certificate. He has served on numerous committees and commissions to the UNEP and other international organizations, and has authored dozens of scientific papers.

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