ecosystems is more complex because of the diversity of biota, i.e., diversity of
biological “targets” of chemicals (Blaha and Holoubek 2013).
Toxicity and ecotoxicity are two types of chemical hazards that are currently
dealt with and evaluated separately. Despite many similarities and parallels, toxicology and ecotoxicology pursue different goals and maintain different focuses.
• The effects of environmental pollutants on human health include relevant
exposure scenarios like use of contaminated drinking water, inhalation of polluted air, or ingestion of food with toxicants accumulated through food chains
(US EPA 2011). Documented adverse outcomes in exposed individuals may be
acute health effects and even human death but—more commonly—chronic
impacts such as developmental or metabolic diseases, reproductive failure, immunosuppression or cancer can occur. Hazards to individual humans are characterized by traditional toxicological models like rodents, dogs, pigs, or monkeys
and the results of toxicological testing are expressed as LD50 (lethal dose to 50%
of the tested organisms) or NOAEL (no observed adverse effect level).
• Environmental contaminants also cause adverse effects to aquatic and soil biota
including microorganisms (Cravo-Laureau et al. 2017; Ghiglione et al. 2016;
Roose-Amsaleg and Laverman 2016; van Beelen and Doelman 1997; Yadav
et al. 2016), algae and higher plants (Sandermann 2004), invertebrates (Cattaneo
et al. 2009; Cortet et al. 1999; Frampton et al. 2006; Kammenga et al. 2000;
Korsloot et al. 2004; Lagadic and Caquet 1998) as well as vertebrates like fish,
amphibians, birds, and even mammals (Carvalho et al. 2014, Maier et al. 2015,
Oprsal et al. 2015, Isidori et al. 2016). By affecting natural biodiversity and
functionality of ecosystems, the effects may propagate further by impairing “ecosystem services”. Thus, the assessment of ecotoxicity, i.e., hazards of chemicals to
integrity and functionality of natural populations and communities of non-human
biota, is of essential importance (Newman 2014; Walker et al. 2012).
In this chapter, ecotoxicology of environmental pollutants is covered with the
aims to (i) provide introductory insights into the effects of chemicals in biological
systems, (ii) outline the concepts and methods in the assessment of ecotoxicity, and
(iii) provide an overview of reported impacts of major water and soil contaminants.
27.2 Biological Effects of Environmental Pollutants
Before discussing practical issues of ecotoxicity testing, it is essential to have good
and common understanding of relevant terms such as toxic effect, adverse
outcome, etc.
First, the central so-called cause–effect paradigm is the red line for both
toxicology and ecotoxicology. “All things are poison and nothing without poison.
Solely, the dose determines that a thing is not a poison” (Paracelsus 1493–1541).
Whenever “toxicity” or “effect” is mentioned in this chapter (e.g., death of an
earthworm owing to acute poisoning by arsenic, cytotoxicity caused by benzo[a]
550
L. Bláha and J. Hofman
biological “targets” of chemicals (Blaha and Holoubek 2013).
Toxicity and ecotoxicity are two types of chemical hazards that are currently
dealt with and evaluated separately. Despite many similarities and parallels, toxicology and ecotoxicology pursue different goals and maintain different focuses.
• The effects of environmental pollutants on human health include relevant
exposure scenarios like use of contaminated drinking water, inhalation of polluted air, or ingestion of food with toxicants accumulated through food chains
(US EPA 2011). Documented adverse outcomes in exposed individuals may be
acute health effects and even human death but—more commonly—chronic
impacts such as developmental or metabolic diseases, reproductive failure, immunosuppression or cancer can occur. Hazards to individual humans are characterized by traditional toxicological models like rodents, dogs, pigs, or monkeys
and the results of toxicological testing are expressed as LD50 (lethal dose to 50%
of the tested organisms) or NOAEL (no observed adverse effect level).
• Environmental contaminants also cause adverse effects to aquatic and soil biota
including microorganisms (Cravo-Laureau et al. 2017; Ghiglione et al. 2016;
Roose-Amsaleg and Laverman 2016; van Beelen and Doelman 1997; Yadav
et al. 2016), algae and higher plants (Sandermann 2004), invertebrates (Cattaneo
et al. 2009; Cortet et al. 1999; Frampton et al. 2006; Kammenga et al. 2000;
Korsloot et al. 2004; Lagadic and Caquet 1998) as well as vertebrates like fish,
amphibians, birds, and even mammals (Carvalho et al. 2014, Maier et al. 2015,
Oprsal et al. 2015, Isidori et al. 2016). By affecting natural biodiversity and
functionality of ecosystems, the effects may propagate further by impairing “ecosystem services”. Thus, the assessment of ecotoxicity, i.e., hazards of chemicals to
integrity and functionality of natural populations and communities of non-human
biota, is of essential importance (Newman 2014; Walker et al. 2012).
In this chapter, ecotoxicology of environmental pollutants is covered with the
aims to (i) provide introductory insights into the effects of chemicals in biological
systems, (ii) outline the concepts and methods in the assessment of ecotoxicity, and
(iii) provide an overview of reported impacts of major water and soil contaminants.
27.2 Biological Effects of Environmental Pollutants
Before discussing practical issues of ecotoxicity testing, it is essential to have good
and common understanding of relevant terms such as toxic effect, adverse
outcome, etc.
First, the central so-called cause–effect paradigm is the red line for both
toxicology and ecotoxicology. “All things are poison and nothing without poison.
Solely, the dose determines that a thing is not a poison” (Paracelsus 1493–1541).
Whenever “toxicity” or “effect” is mentioned in this chapter (e.g., death of an
earthworm owing to acute poisoning by arsenic, cytotoxicity caused by benzo[a]
550
L. Bláha and J. Hofman