User:ShawnInnocent99/Environmental impact of the petroleum industry

Microplastics
Microplastics are particles that are smaller than 5 mm in size. These microplastics are ingested by the marine wildlife and it ends up in the food-web which is a concern because they have a tendency to adsorb pollutants on their surface. Microplastics are also a concern due to their ability to accumulate. When these particles are ingested by organisms they usually end up in tissues such as the digestive glands, circulatory system, gills and guts. When these organisms are consumed and shifted upwards in the food chain, they end up creating an exposure risk towards bigger organisms and ultimately humans. Microplastics possess many risks to various organisms. They are known to disrupt algal feeding, increase mortality and lower fertility in copepods. Amongst mussels, microplastics are known to interrupt filtration and induce inflammatory responses. There is still a lack of data in how these particles ultimately affect humans because most marine organisms are gutted before consumed. In spite of that, their environmental effects are well documented and the extent of their damage is well understood.

Produced water and drilling waste discharges
Main article: Produced water Produced water (PW) discharges from petroleum extraction results in PAH (Poly-aromatic Hydrocarbon) emission in the ocean. Approximately 400 million tons of PW discharge is released annually from oil-fields in the North Sea, UK and Norwegian discharges combined. PW discharge is the largest emission event in the marine environment world and it is a result of offshore oil and gas production. The composition of materials in the PW depends on the characteristics of the region. However, PW mainly contains a mixture of a few select products such as formation water, oil, gas, brine water and added chemicals. Just like PW, formation water composition also depends on its surroundings although, it mainly consists of dissolved inorganic and organic compounds. PW was responsible for releasing 129 tons of PAHs in 2017. Due to the presence of harmful chemicals in PW, it is responsible for evoking toxic responses in the surrounding environment. For example, surveys done in the Norwegian Continental Shelf (NCS) found that PAHs released by PW were responsible for biological changes in mussel and Atlantic cod. Formation of PAH burden caused DNA damage and digestive-gland histochemistry in mussel. PAHs also pose a serious threat to human health. Long term exposure to PAHs have been linked to a series of health problems such as lung, skin, bladder, gastrointestinal cancer.


 * 1) Added a citation: https://doi.org/10.1016/B978-0-12-409548-9.11246-1