The negative impact of the cotton gin in Texas primarily included increased need for slave labor. The invention of the cotton gin made the process of separating cotton fibers from seeds much more efficient, leading to a significant increase in cotton production. This demand for increased production resulted in a greater reliance on enslaved labor to cultivate and harvest the cotton, perpetuating and intensifying the system of slavery in the region.
Additionally, while the statements about water supply and pollution may be valid issues in the broader context of agriculture, the most direct negative impact associated specifically with the cotton gin in terms of social and economic systems was the increased reliance on slave labor.