Israel’s new environment minister, Dalia Itzik, on Monday toured the blighted Gaza Strip with her Palestinian counterpart, Yousef Abu Safieh, marking the beginning of what they hope will be an era of cooperation in addressing the region’s environmental woes. Discussion between the two was polite, but each side pointed to problems the other had caused. Abu Safieh said Israeli companies were illegally dumping toxic chemicals on Palestinian land, and asked why Israel was permitting environmentally unsound construction inside the West Bank. Members of Itzik’s staff said Palestinians are dumping raw sewage into the harbor and letting waste seep into the area’s underground aquifer.