na i ,” ▁said ▁Dr ▁Rak hal ▁G ait onde , ▁a ▁public ▁health ▁special ist . ▁ ▁According ▁to ▁the ▁report ▁by ▁the ▁Coast al ▁Resource ▁Centre , ▁the ▁level ▁of ▁mang an ese ▁in ▁eight ▁of ▁the ▁eleven ▁samples ▁exceed ▁the ▁US ▁E PA ▁reference ▁concentration ▁for ▁expos ure ▁to ▁mang an ese . ▁There ▁are ▁no ▁standards ▁in ▁India ▁for ▁mang an ese ▁in ▁ambient ▁air . ▁Also , ▁the ▁levels ▁of ▁calci um ▁sil icon ▁and ▁cry st all ine ▁sil ica , ▁which ▁are ▁en rich ed ▁in ▁coal ▁ash ▁were ▁found ▁in ▁the ▁air ▁samples . ▁ ▁“ M ang an ese ▁and ▁Nick el ▁are ▁well ▁known ▁to x ins ▁and ▁their ▁effects ▁are ▁well ▁documented . ▁Mang an ese ▁is ▁pre domin antly ▁ne uro ▁to x in , ▁while ▁nick el ▁is ▁a ▁car cin ogen . ▁The ▁measurement ▁of ▁such ▁to xic ▁subst ances ▁from ▁the ▁ro o ft ops ▁of ▁human ▁settlement s ▁is ▁indeed ▁a ▁cause ▁of ▁concern ,” ▁added ▁Dr . ▁Rak hal . ▁ ▁The ▁Coast al ▁Resource ▁Centre ▁wants ▁the ▁T amil ▁N adu ▁government ▁to ▁take ▁immediate ▁action ▁to ▁improve ▁the ▁air ▁quality ▁in ▁En n ore . ▁“ The ▁government ▁needs ▁to ▁imp ose ▁a ▁mor ator ium ▁on ▁all ▁industrial ▁activities ▁till ▁the ▁environment ▁is ▁restored , ▁initi ate ▁long - term ▁and ▁continuous ▁monitoring ▁in ▁En n ore ▁region ,” ▁said ▁N ity an and ▁Jay aram an , ▁an ▁environment ▁activ ist .