This paper analyzes the effects of technological risk on long-run growth when labor supply is elastic and production gives rise to a pollution externality. We show that the randomness of production, as well as the endogeneity of labor supply, affects the equilibrium solutions for the social planner and for the market economy. We analyze the effects of environmental policy, discuss conditions for an optimal policy, and find that the response of labor supply to changes in the model parameters and to variations in the policy instruments crucially depends on the volatility of output.