This paper investigates the impact of local traffic pollution on the formation of residential and business districts. While firms benefit from local production externalities, households commute to their workplaces with private vehicles and exert a local pollution externality on the residents living along the urban transport networks. The spatial location of firms and residents endogenously results from the trade-off between the production and pollution externalities and the commuting costs. The analysis shows that in monocentric cities the benefits associated with a fall in per-vehicle pollution are absorbed by rents paid to absentee landlords. When a city includes business and residential districts as well as a district mixing both agents, a lower per-vehicle pollution enlarges the residential districts and shifts the business districts closer to the geographical center of the city. The paper finally studies the optimal city structure. The first-best policies that fully internalize the externalities still foster business agglomeration.

本文研究了当地交通污染对居民区和商业区形成的影响。当企业从当地生产的外部性中受益时，家庭则使用私家车通勤到他们的工作场所，并对居住在城市交通网络中的居民施加局部性的污染外部性。企业和居民的空间定位是内生于生产和污染外部性与通勤成本之间的权衡。分析表明，在单中心城市，与整车污染下降相关的收益被支付给缺席房东的租金所吸收。当一个城市包括商业区和居民区以及混合了这两个代理人的地区时，较低的车辆污染会扩大居民区，并使商业区更靠近城市的地理中心。最后研究了最优城市结构。完全内部化外部性的最佳政策仍然可以促进业务集聚。