benefical or harmful element
concentration of harmful substance
danger and harmful factor
dangerous and harmful factors
detection of harmful substances
environmentally harmful
forestry harmful biology
frequent harmful algal bloom areas
harmful
有害
危害
有
赤潮
不良
赤
敌害
有毒
有害辐射
不利
有害的
药害
危害性
Harmful agricultural product
harmful algae bloom HAB