Poly-drug abuse, or polydrug use, refers to the consumption of more than one drug or type of drug by an individual, often simultaneously or sequentially. This behavior is typically driven by the desire to enhance the effects of one substance, mitigate the side effects of another, or simply to maintain a persistent state of intoxication or dependence, which significantly increases health risks.

Soil pollution and degradation involve the loss of soil quality or utility. Soil erosion refers to the removal of topsoil, while desertification involves the degradation of land in arid or semi-arid areas. Both processes negatively impact the environment and soil health, making them significant concerns in environmental sociology and geography.

Climate change refers to significant, long-term changes in the global climate, including temperature and precipitation patterns. While natural factors contribute, contemporary climate change is largely driven by human activities such as the burning of fossil fuels, which increase greenhouse gas concentrations in the atmosphere, leading to global warming and broader environmental shifts.

New-style terrorism is characterized by global aims, decentralized or loose organizational structures, and increased ruthlessness. Unlike traditional terrorism, which was often rooted in specific nationalist or separatist ideologies seeking to establish a state, new-style terrorism is frequently driven by transnational religious or ideological goals that transcend national boundaries, making the nationalist focus less relevant to its modern manifestation.

While modern sociology has integrated environmental concerns, the classical theorists—Marx, Durkheim, and Weber—primarily focused on industrialization, social solidarity, and rationalization. Although some scholars argue that elements of their work can be applied to environmental sociology, none of them treated environmental issues as a central or primary focus of their sociological inquiry.

Drug use is a complex social phenomenon often linked to various factors. Sociological research indicates that individuals may turn to substances due to structural stressors like unemployment, psychological needs for stress relief or 'peace of mind,' or social motivations related to recreation and pleasure-seeking behaviors.

Manufactured risks are hazards created by human activity and technological advancement, such as climate change or nuclear proliferation. Conversely, volcanic eruptions are natural phenomena that occur independently of human intervention, making them external risks rather than manufactured ones.

Social disorganization theory, developed by the Chicago School, posits that crime and deviance are more likely to occur in communities with weak social ties and the absence of social institutions. When a neighborhood lacks the ability to regulate itself through shared values and informal social control, deviant behavior becomes more prevalent among its residents.

Global warming refers specifically to the long-term increase in the average temperature of the Earth's climate system. While it is closely linked to the greenhouse effect—a natural process where gases trap heat—the term 'global warming' describes the observed trend of rising surface temperatures primarily driven by human activities, such as the burning of fossil fuels and deforestation, which enhance the greenhouse effect beyond natural levels.

Environmental sociology investigates the complex interactions between human social systems and the natural environment. It explores how social structures, cultural values, and economic systems impact ecological health, and conversely, how environmental changes influence social organization and inequality. This field is increasingly vital for understanding issues like climate change, resource depletion, and the social movements dedicated to environmental sustainability and justice.