Historical Perspective –Contamination
Environmental contamination of the land is not a new concept. There is evidence that Roman smelters contaminated the land with lead which effect most of Europe (Ferrara, 2020). In the mid-20th century synthetic materials such as plastics, polychlorinated biphenyls (PCBs), and inorganic pesticides like dichlorobiphenyl trichloroethane (DDT) began to be produced (Ferrara, 2020). They had toxic properties and did not degrades in the environment over time. Chemical spills, toxic gas releases, petroleum product spills and leaks, as well as They also presented health risks as well as risks to the biodiversity of ecosystems. These developments also increased the potential for large scale industrial accidents, hazard waste illegal dumping, and increased pollution of the air and water as well as the land. In 1962 Rachel Carson wrote the Silent Spring a book that focused attention of the world on the growing environmental problems presented by pesticides like DDT. Government around the world began implementing laws that restricted the use of many contaminants but much of the damage was already done. In 1970 the Environmental Protection Agency (EPA) was established to which combined a variety of other regulator and oversight agencies to provide a more efficient means of protecting the environment. In wake of environmental disasters such a major environmental disaster in New Jersey in 1977 and Love Canal, which highlighted the health risks of hazardous waste dumping in New York in 1978, the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or Superfund) was established. According to the EPA Superfund, Brownfield, and RCRA Sites in the U.S. (U.S. EPA, 2013) while it is known there is extensive land contamination in the U.S. the extent of land contamination is not available (EPA, 2018). “Pollution of the environment keeps on increasing at an alarming rate due to the activities of man such as urbanization, technological advancement, unsafe agricultural practices and rapid industrialization which degrades the environment.” (Ojuederie & Babalola, (2017). The challenge becomes how to remediate the current and future damage to the environment done by known and unknown environmental contaminants (EPA, 2019).
Environmental Remediation from Backhoe to GMO’s
In the early year of environmental remediation techniques such as incineration, soil removal and replacement, soil washing, and oxidation along with numerous other strategies were used to remediate hazardous waste contamination (Shifrin, 2020). Many didn’t work or presented challenges such as where to put the excavated contaminated soil. Moving contaminants from one place to the other did solve the problem. This earth has a limited supply of natural resources such as land and water. The ultimate goal of environmental remediation is to restore the site to a “clean” condition and put the land, for example, back into a usable condition. Many laws and regulations are on the books today that address environmental contamination. Going forward it is critical that there is no further contamination and that the current sites be remediated. The current range of remediation techniques include slurry phase biological treatment, , in situ chemical oxidation, and bioremediation (Treatment Technologies Screen Matrix, 2007). These techniques while being effective in some cases come with drawbacks. Slurry phase requires excavation of the soil and then treatment in a bioreactor where microorganisms that assist in the process of “cleaning” the soil of contaminants (Slurry Phase Biological Treatment, n.d.). After biodegradation is complete the clean slurry can be put back into the environment. Chemical oxidation is a process using oxidizing agent like ozone or chlorine to eliminate or reduce the hazardous condition of the soil (Chemical Oxidation, n.d.). These remediation techniques come with their own set of challenges and often don’t total solve the problem. Bioremediation provide an alternative to many of the remediation techniques because they can be done in situ with no excavation and resulting in “clean”soil that can be reused. Microorganisms can be used to mitigate soil and groundwater contamination. The microorganisms are introduced and use the contaminant as a resource for food and energy (In Situ Biological Treatment for Soil, Sediment, Bedrock and Sludge, n.d.). Bioaugmentation is involves the breeding of microorganisms that address specific types of contaminants. Genetically modified organisms (GMOs) can provide a target safe efficient alternative to other popular techniques.
History of Genetically Modified Organisms (GMO’s) for Environmental Remediation
In 1973 the biotechnology world developed GMO’s. Over the years advances in this field have included GM crops that can resist drought, advances in drug therapies, manipulation of human and animal genes, and GMO’s that can assist in environmental remediation. There are naturally occurring microorganisms that can degrade contaminants which have been used to understand the metabolic pathways related to the process of bioremediation (Kumar, Dagar, Khasa, & Kuhad, 2013). Genetically engineered microorganisms (GEMs) use techniques that modify the organism and its enzymes for better efficiency in degrading persistent organic pollutants (POPs) (Kumar et al, 2013). According to the World Health Organization “Persistent organic pollutants (POPs) are chemicals of global concern due to their potential for long-range transport, persistence in the environment, ability to bio-magnify and bio- accumulate in ecosystems, as well as their significant negative effects on human health and the Gabriel Rangel | Science in the News | August 12, 2015 environment” (Persistent organic pollutants (POPs). n. d). Common POPs include polychlorinated biphenyls (PCBs) and pesticides (Kumar et al, 2013.). Suicidal-GEMs (S-GEMs) which were developed recently present another safe and effective way to use GMO’s in environmental remediation. Sustainability is another important factor in the environmental remediation process. Plants and their enzymes are being used to provide an environmentally compatible and sustainable technique (Saxena, Kishor, Saratale, & Bharagava, 2020). Ideally trees used for phytoremediation should be able to absorb large amounts of contaminants, grow in contaminated soil, have a high biomass, and grow quickly (Pocket K No. 25 Biotech Plants for Bioremediation, 2020). The majority of trees that can live in toxic soil do not meet the other requirements while those that meet other requirements can’t tolerate pollutants. (Pocket K No. 25 Biotech Plants for Bioremediation, 2020). The answer is the development of genetically modified plants with tolerance to pollutants that are given the necessary traits such a good accumulation of contaminants and effective uptake (Pocket K No. 25 Biotech Plants for Bioremediation, 2020). Some plants have a natural resistance to toxic metal due to specific proteins. Genetic engineering can improve phytoremediators, plants used in phytoremediation, by coding for these proteins. Explosives and products of their degradation provide a risk to human and the environment. Tobacco plants have been engineered to have a tolerance to these contaminants and are able to remediate TNT. Other plants have been engineered to be resistant to RDX, an explosive used in World War II that still is contaminating sites today (Pocket K No. 25 Biotech Plants for Bioremediation, 2020). There are numerous other toxins that need remediation including mercury, herbicides, and arsenic which can be done through GMO’s. There seems to be no question as to whether GMO’s should be used for environmental remediation based the science and the benefits provided to living things and the environment but there are challenges to this assumption.
Does the Means Always Justify the End?
The environment is at a critical juncture. In the past the industrial age brought great opportunities but at what price. The environmental impact of what was seen as great strides for society ended up being disastrous. Today society must clean up what has been left behind. The land in contaminated, the air polluted, and drinking water at is risk. Was pursuing every advance made without thinking about the consequences prudent? Plastics were embraced by society but at what cost? This may be one reason that society is skeptable of biotechnological advances in recent years.
GMO’s are a subject that present concerns for many sectors of society. In order to move forward not only the science of GMO’s and environmental remediation but its impact on societal and ethical concerns must be considered.
The debate regarding GMO’s often divides the scientific community and the general public. The scientific community bases its conclusions on scientific evidence while other may rely on internet or media sources for their “facts”. The gene manipulation especially as related to humans is seen by many in relation to science fiction. There are those that have religious objections to “playing God”. Environmentalists are concerned about the introduction of altered gene into the environment (The benefits and risks of GMO’s, 2020). However, where are these concerns coming from. Much of the information that the public receives about GMO technology comes from the internet and media which can be “inaccurate, incomplete, or misleading” (Wunderlich & Gatto, 2015). Education is a vital part of introducing the public to GMO’s technology and in shaping societal and ethical views in the future.
With the introduction of new biotechnological advance there are impacts of society. These impacts can be positive or negative and are often dependent upon the perception of the individual. The value of GMO’s including in environmental remediation bring up a range of pro and cons that can be considered. One societal issue is what might be the health implications of genetic engineering. It can be a valuable tool in the area of health and treatment. Patient with diabetes for example that cannot produce sufficient insulin can benefit from GM technology. Their genes can be implanted into another species such as a sheep or goat which uses the genetic information to produce insulin (Biology Wise, n.d.) Neo-organs can be created through genetic engineering to be used to develop new organs that increase the available pool for transplantation (Biology Wise n.d.). Additionally, GM crops have been developed that can improve health by delivering digestible iron to those in need (Oliver, 2014). Many people in the population are affected by allergens resulting in minor to severe reactions. There are concerns that exposure to GMO’s foods present a greater risk than non-GMO food. According to the World Health Organization (WHO), the Food and Agriculture Organization of the United Nations (FAO) and WHO agree “no allergic effects have been found relative to GM foods currently on the market” (WHO, 2014). Will the exposure to GMO’s allow for the transfer of gene to humans or other living things causing mutations in their genes (Acker, Rahman, & Cici, 2017)? Clusters of regularly interspaced short palindromic repeats (CRISPER) technology offers an opportunity to overcome concerns about foreign DNA because of its ability to address specific targets. ((Acker, Rahman, & Cici, 2017). During the GM process there may be an interference with natural reproduction of organisms. This could either increase reproduction and risk an overabundance of an organism or impact future populations and present the risk of extinction (Acker, Rahman, & Cici, 2017).
Genetically modified plants provide crops that can carry traits such as drought resistance or pest resistance. This can increase crop yields and reduce the need for dangerous pesticides. “Herbicide tolerant crops have facilitated the continued expansion of conservation tillage, especially no-till cultivation system, in the USA. The adoption of conservation and no-till cultivation practices saved nearly 1 billion tons of soil per year” (Pocket K No. 4: GM Crops and the Environment, 2020). A 2014 report analyzing the increased productivity of farmers with the use of GMO technology indicated that due to either productivity or financial returns chemical pesticide use decreased by 37%, profits increased by 68%, and yields increased by 22% (Klumper & Qaim, 2014). Toxic metals can present a risk to both human health and the environment. By accumulating in the soil these metals can enter the food chain and be ingested by human and other living things (Ojuederie & Babalola., (2017).