The concentrations found for each NSAID constitute highly relevant information
for the design of ecotoxicity studies in different species based on “environmentally
relevant” levels. This in turn will favor the establishment of permissible limit values
for specific NSAIDs and, on the other hand, will direct the development of water
degradation, treatment, or purification methods capable of truly solving the problem.
The worldwide distribution of studies on the subject is practically concentrated in
Asia and Europe, although research is still isolated and dispersed and is carried out
by very specific research groups around the world. This does not mean that following the precautionary principle, the evidence already available should not be used to
reinforce regulations and continuous monitoring by all environmental regulation
agencies in different countries. Pollutants do not know about political borders, much
less in the case of water. However, and despite all the evidence that has been
published for more than a decade, regulation on pharmaceuticals discharges and
environmental risk assessment remain largely unchanged.
Analytical methods have been optimized to become increasingly sensitive and
capable of quantifying a large number of substances from the same sample even if it
can be a complex mixture. However, the need to develop easy-to-apply methods,
even portable, but also with good sensitivity, was evident so that they can be used
directly at the sampling sites thereby optimizing routine monitoring.
The fate of pharmaceutical products and their metabolites in surface and groundwater is still incompletely understood, especially since the results and knowledge
generated through laboratory experiments cannot be translated with complete reliability to the real world.
Moreover, at the end of this review, we also realized that comprehensive studies
are needed to monitor the concentrations of the highest consumption NSAIDs from
wastewater, through the treatment plants and following their course to rivers, lakes,
groundwater, seas, or drinking water where they flow depending on each region. The
foregoing would allow a better understanding of the conditions that favor or hinder
the gradual disappearance of said compounds throughout their journey in the
environment. In turn, this information would be very useful for monitoring the
toxicity in sentinel organisms.
From a global perspective, the problem is undoubtedly very complex because
different mixtures of pollutants coexist whose composition is dynamic because it
depends on phenomena of biotic and abiotic degradation, water flows,
pseudopersistence, predominance of certain stereoisomers to stay in the compartments or bioaccumulate, and, of course, the effects of climate change.
Finally, despite the fact that the published studies concentrate on very few
countries and regions of the world, this review shows that the contamination of
surface waters by NSAIDs is not an exclusive problem of industrialized countries
and of those with developed markets, since the presence of these products was
detected in various effluents around the world. Even when some countries have more
developed policies and regulations, these efforts are diluted and lose impact when
they share natural resources with other countries that control and monitor the
pollution very poorly. Due to this, the objectives and actions undertaken to avoid
the occurrence of medicinal products as water pollutants must be globally
78
L. I. Castro-Pastrana et al.
for the design of ecotoxicity studies in different species based on “environmentally
relevant” levels. This in turn will favor the establishment of permissible limit values
for specific NSAIDs and, on the other hand, will direct the development of water
degradation, treatment, or purification methods capable of truly solving the problem.
The worldwide distribution of studies on the subject is practically concentrated in
Asia and Europe, although research is still isolated and dispersed and is carried out
by very specific research groups around the world. This does not mean that following the precautionary principle, the evidence already available should not be used to
reinforce regulations and continuous monitoring by all environmental regulation
agencies in different countries. Pollutants do not know about political borders, much
less in the case of water. However, and despite all the evidence that has been
published for more than a decade, regulation on pharmaceuticals discharges and
environmental risk assessment remain largely unchanged.
Analytical methods have been optimized to become increasingly sensitive and
capable of quantifying a large number of substances from the same sample even if it
can be a complex mixture. However, the need to develop easy-to-apply methods,
even portable, but also with good sensitivity, was evident so that they can be used
directly at the sampling sites thereby optimizing routine monitoring.
The fate of pharmaceutical products and their metabolites in surface and groundwater is still incompletely understood, especially since the results and knowledge
generated through laboratory experiments cannot be translated with complete reliability to the real world.
Moreover, at the end of this review, we also realized that comprehensive studies
are needed to monitor the concentrations of the highest consumption NSAIDs from
wastewater, through the treatment plants and following their course to rivers, lakes,
groundwater, seas, or drinking water where they flow depending on each region. The
foregoing would allow a better understanding of the conditions that favor or hinder
the gradual disappearance of said compounds throughout their journey in the
environment. In turn, this information would be very useful for monitoring the
toxicity in sentinel organisms.
From a global perspective, the problem is undoubtedly very complex because
different mixtures of pollutants coexist whose composition is dynamic because it
depends on phenomena of biotic and abiotic degradation, water flows,
pseudopersistence, predominance of certain stereoisomers to stay in the compartments or bioaccumulate, and, of course, the effects of climate change.
Finally, despite the fact that the published studies concentrate on very few
countries and regions of the world, this review shows that the contamination of
surface waters by NSAIDs is not an exclusive problem of industrialized countries
and of those with developed markets, since the presence of these products was
detected in various effluents around the world. Even when some countries have more
developed policies and regulations, these efforts are diluted and lose impact when
they share natural resources with other countries that control and monitor the
pollution very poorly. Due to this, the objectives and actions undertaken to avoid
the occurrence of medicinal products as water pollutants must be globally
78
L. I. Castro-Pastrana et al.