…the presence in or introduction into the environment of a substance which has harmful or poisonous effects…
…the presence in or introduction into the environment of a substance which has harmful or poisonous effects…
…the presence in or introduction into the air of a substance which has harmful or poisonous effects…
…brightening of the night sky caused by street lights and other man-made sources, which has a disruptive effect on natural cycles and inhibits the observation of stars and planets…
…the spread of altered genes from genetically engineered organisms to other, non-engineered organisms, especially by cross-pollination…
…the controversial problem of pollution…
