Industrial pollution has adversely affected biodiversity for the last two centuries and continues to increase globally. The effect most closely correlated with loss of ecosystem services is toxification of environmental sites, whereby the organisms living in the ecosystem are damaged because of the poisonous nature of many pollutants. As many toxicants (poisonous materials) can act even with very minimal exposure, it is almost impossible and economically infeasible to remove dissolute pollution from the environment with modern technical methods. Only spatially and temporally concentrated pollution can be retracted effectively by anthropogenic efforts, and such methods are already in use in such projects as the U.S. Superfund, a program implemented by the U.S. Environmental Protection Agency (EPA) to contain hazardous pollution and restore polluted sites. Any dissolute pollution (pollution present in low concentrations in aquatic systems) cannot be removed efficiently by human efforts since such large areas are affected and must therefore be removed through natural biodegradation. The only way to restore biodiversity to areas affected by dissolute pollution is to remove the sources of pollution, make sure that toxic buildups can be naturally removed through chemical, physical and biological processes (Alexander, 2000) and ensure that pollution-intolerant organisms have access to recolonize the area. The process, especially of the last two steps, is very time-consuming; it may take 10 to 50 years to increase biodiversity in the system and rebuild ecosystem services (Langford et al., 2010), as evidenced from cleanup efforts in the U.S. and the U.K.
To evaluate solutions to pollution, it may be helpful to distinguish between different kinds of industrial pollution. A first and common distinction is between sources of pollution: point sources, which are spatially and temporally defined such as a factory, and non-point sources, which are impossible to locate or confine such as household emissions (Auty, 1997). Only point sources can be effectively reduced by treatment of waste due to the possibility of regulation, whereas lessening the overall consumption will affect both point and non-point sources. Another distinction may be chosen between the use of the pollutant: agrochemicals, industrial organic and inorganic waste, and household emissions of chemicals.
Organic and inorganic wastes are releases of large amounts of the most ecotoxic materials such as heavy metals, ammonia, cyanide, volatile organic compounds, halogenated organic compounds and arenes (U.S. EPA, 2011). Release of these chemicals into the environment is not intentional; that is, the release of these chemicals is not required in order for any process to work.
Because agrochemicals are intentionally released into the environment, prohibiting their usage would probably not be politically or economically feasible. This kind of regulation would significantly raise food prices and incur food shortages and famines because pests would destroy a significant amount of the crop yield. A feasible solution should include both reduction of use and shifts to less chronically toxic products. As such a solution may lead to a reduction of crop yield and will definitely require farmers in industrialized countries to change their habits, it can only be implemented through enforced government regulations. To make decisions about how to regulate agrochemicals, governments will need objective data on the damage pollutants pose to environments.
Data on ecotoxicity was historically accumulated by reviewing polluted sites and comparing them to pristine sites or to historical data, but this comparison is sometimes difficult due to the absence of truly pristine sites (Grant et al., 2010). Where pollution has already been released into the environment, circumstances previous to the pollution are difficult to extrapolate. Instead, the U.S. EPA takes a preemptive approach to minimizing damage to ecosystems from pesticides by requiring chemical industries to register new pesticides for use. According to EPA policy, pesticides need to pass a series of tests demonstrating that they are not "unreasonably" harmful to the surrounding ecosystems (concerning both their toxicity and their degradability). The EPA does not conduct these tests but reviews research that needs to be submitted before a product can be sold on the market (U.S. EPA, 2011). This research is put into models which classify the product's bioavailability to organisms in the environment and its relative toxicity (U.S. EPA, 2011). However, these models are only available for pesticide use; many other pollutants do not have such extensive toxicity data, which makes it difficult to assess the effects on the environment before pollution.
While expansive toxicity databases exist for most laboratory materials, agrochemicals and heavy metal compounds, such data is only just being accumulated for household, medicinal and other regularly applied chemicals and has not yet resulted in governmental regulations even though the amount of use may be considered a valid concern (Tillet, 2009). However, compared to other types of chemical pollutants, most household and medical chemicals do not have comparable ecotoxicity and are less harmful due to environmental concentrations on the parts per trillion scale.
There are two approaches through which pollution can be reduced:
Yet waste treatment can only be effective if pollution is coming from a defined and accessible source (point source).
Many countries, including the E.U., Switzerland, Canada and the U.S., have effectively implemented systems that treat waste water for most chemicals, yet significant improvement in methods are possible. In such improvements, priority should be given to considering the use of microbes or fungi for cleanup of heavy metals and organic compounds that are hard to degrade because of their high efficiency relative to chemical or physical methods (Christensen, 1989). Most developing and threshold countries lack treatment facilities (World Bank, WDI, 2006), meaning waste waters in these countries are significantly more toxic per unit mass then waste water in developed countries, which is also a result of companies shifting pollution-intensive production to countries with fewer environmental restrictions. This is especially observed in the mining industry, where treatment of waste is often very expensive and pollutants are very toxic (Diamond, 2005).
It is often assumed that governmental restrictions or strong consumer pressure are necessary to cause significant reduction in the production of polluting goods, because there is usually no short-term internal benefit to reducing pollution for corporations. The reasons corporations reduce their pollution are based on consumer preference for low-pollution goods and the high cost of noncompliance with environmental regulations (Innes & Sam, 2008). But reducing pollution does not only mean treating waste or paying for waste removal, which only raises costs. Research suggests that preventing pollution during the production process by reducing use of pollutants or implementing low-use techniques actually increases efficiency and financial performance of private corporations by an additional 5 to 8 percent over five years (King & Lenox, 2002).
Consumers and governments need to do their part to push companies to decrease pollution. Although pollution prevention can provide a financial incentive for private corporations, consumer pressure is still necessary to develop company awareness of pollution issues. To implement standards throughout a pollution-intensive industry, a government agency must implement environmental regulations. Regulations could include a levy or tax plan which would make polluters pay a fixed amount of money for pollution, a cap-and-trade system which would fix the amount of emissions, prescription of maximum releases, or minimum waste reduction techniques. Such regulations might come with a high cost to production if no comparable alternatives are available and efficiency measures are already exploited. However, according to a study by King and Lenox (2002), efficiency measures are underestimated by at least 30 percent of managers. The potential for development of efficiency has resulted in a small industry of efficiency counseling, which could be helpful in eliminating unnecessary pollution from industrial processes. In general, government regulations need to be stronger in order to eliminate such industrial overuse of pollutants and provide incentives for research and implementation of more efficient techniques. The exact guidelines must be determined by case, as different pollutants have different effects and can be reduced by different measures, which warrants different approaches.
A long-term solution that could reduce pollution from agricultural chemicals is research into more sustainable methods of farming large amounts of food, such as ecosystem engineering or biomimicry. This research focus is necessary for an eventual transition to non-polluting agriculture, which is not feasible now because current methods don't work. However, non-polluting agriculture will eventually become necessary, because all pesticides are by definition poisons; indefinitely relying on them is not a solution that will generate integrated ecosystems, which are necessary to eventually increase biodiversity while keeping high yields.
Other organic materials are often not quite as toxic as pesticides, yet studies have found that degraded forms of dichlophenac, a common painkiller, have caused the loss of kites, a carrion-eating bird, in Pakistan and India (Oaks et al., 2004). Organic solvents can also have high toxicity values, making them ecologically significant as well. Unlike agrochemical pollution, which occupies too much area and includes too many possibilities for runoffs to be modeled as a point source, most other organic chemicals released to the environment are gathered in waste disposals of urban or industrial sewage systems and can theoretically be treated. For effective treatment, the proper degrading microbes as well as enough time are necessary, which means that extensive treatment plants should be developed for many countries. This treatment could take the form of microbial degradation plants commonly used in industrialized countries or, if sufficient space were available, constructing degrading wetlands could be a cost-effective alternative.
In the case of pollution leading to buildup of toxic material, reduction of availability to the environment must be ensured to rebuild ecosystem services in a polluted area. Although physical or chemical methods such as change in acidity or absorption into the soil can help decrease the availability of chemicals, additional monitoring and securing is necessary to make sure that the pollutant is not brought back into the environment. Ideally, the system should be able to degrade the pollutant by microbes or fungi, as this will irreversibly destroy the toxicant.
Many inorganic materials take a long time to biodegrade, which means that their buildup rate is almost proportional to the total rate of pollution at any given time. These are also often some of the most potent and generally poisonous materials and thus strongly toxic even in low concentrations. Influential inorganic pollutants include non-metals like ammonia and cyanide and heavy metals such as Cu, Hg, Cd among others, which are all toxic in various degrees. Many inorganic discharges are point sources, so proper treatment of material is generally possible through biological degradation with microbes and fungi or electrokinetic treatment (the use of electricity to reduce heavy metal ions and turn them into elemental precipitates). Also, most heavy metals are much less toxic in alkaline environments, a fact that can be used in treatment plans. Some combination of these three techniques should be established to lower emissions for point source metal pollution.
After a site has been rid of its toxicity and offers a space in which normal, pollution-intolerant organisms can live, recolonization and reconstruction of the ecosystem need to occur. This recolonization depends on the availability of organisms to refill the parts of the ecosystem that have been destroyed. If a distinct and isolated environment were destroyed, such as pond ecosystem, not all species may be available in close proximity.
Macroorganisms, like mammals, amphibians, or fish, often have their own mechanisms of travel, yet even many of them need connected biomes. On the other hand, many smaller organisms that are essential to the ecosystem, such as small insects or microbes, cannot travel on their own and rely on wind, rain, drift, or transportation by other organisms to change places. Macroorganism travel may be significantly impaired by habitat fragmentation through urbanization, pollution of river biomes all the way to their sources, or an extinction or large reduction in numbers of transporting species such as waterfowl (Yukimura et al., 2009). These obstacles are also often directly correlated to the pollution or the cause of pollution. For instance, strong industrial presence can pollute environments, but will also lead to urbanization and habitat fragmentation due to workers living nearby. If there are no colonies preserved from pre-pollution eras and classical mechanisms of transport have been destroyed for organisms occupying important niches in the ecosystems, careful human intervention may be needed to introduce necessary species.
In conclusion, any action plan to reduce industrial pollution will need to be tailored toward specific pollutants to work well and not pose undue risks on either the economy or the environment. A slightly generalized plan based on the different kinds of solutions available can be proposed for the different pollutants:
Reduction of Pollution:
Detoxification and Recolonization:
Research is necessary for more advanced treatment plans, systems of production that do not use polluting agents and remediation technology. Research should be influenced by key concepts such as integration of ecosystems and biomimicry
