Indeed, some say they believe an element of mystery will always pervade, given the gaps in knowledge about pollutants and their health effects.
Extensive research in urban watersheds has broadened our knowledge about point and non-point pollutant sources, but the fate of nutrients is not completely understood.
The performance, in terms of effluent quality, is believed to be better, but there is a striking lack of knowledge about the behaviour of trace-pollutants.
In fact, the interpretation of an "adequate margin of safety" and what is a "safe" level could depend on the individual, because people may differ in their susceptibility to air pollutants, and could depend on the evolving knowledge about the health impacts of air pollution at low levels (American Thoracic Society 2000).
These challenges include a lack of asthma statistics at the local level, limited exposure information, and a paucity of scientific knowledge about the contributions of hazardous air pollutants to asthma induction or exacerbation.
Knowledge about transport processes and the fate of microbial pollutants associated with rainfall and snowmelt is key to predicting risks from a change in weather variability.
Environmental tobacco smoke, also called secondhand smoke, is an indoor air pollutant in many homes, despite widespread knowledge about the harmful effects of smoking.
In the following sections, we provide brief reviews of the state of knowledge about human/public health outcomes associated with HABs, microbes, and chemical pollutants in the oceans; with flooding and inundation events; and with the consumption of seafood; and we review the implications for management measures and future research priorities.
The study of these transcripts could be useful to increase the knowledge about the physiological and genetic mechanisms activated by mussels in response to toxic pollutants (heavy metals in particular).
In addition to the discrepancy in the relationship between PM exposure and HRV response, there is a lack of knowledge about the health effects due to the potential synergy between PM2.5 and ambient gaseous co-pollutants [ 29].
