. ▁The ▁European ▁Union ▁R isk ▁Ass ess ment ▁Report ▁review ed ▁more ▁than ▁a ▁dozen ▁studies ▁of ▁the ▁to x icity ▁of ▁mus k ▁x yl ene ▁to ▁alg ae ▁and ▁to ▁aqu atic ▁verte br ates ▁and ▁in verte br ates , ▁and ▁all ▁found ▁no ▁observed ▁effect ▁concentr ations ▁greater ▁than ▁ 1 0   µ g / l , ▁the ▁chron ic ▁aqu atic ▁to x icity ▁threshold ▁in ▁the ▁EU ▁RE AC H ▁Reg ulation . ▁ ▁The ▁bi ode grad ation ▁of ▁mus k ▁x yl ene ▁in ▁sea ▁water ▁and ▁in ▁mixed ▁sea ▁water / sed iment ▁systems ▁was ▁studied ▁in ▁labor atory ▁simulations ▁using ▁carbon - 1 4 ▁label led ▁mus k ▁x yl ene , ▁and ▁the ▁results ▁discussed ▁in ▁an ▁add endum ▁to ▁the ▁European ▁Union ▁R isk ▁Ass ess ment ▁Report . ▁The ▁half - life ▁in ▁marine ▁sed iment ▁was ▁estimated ▁to ▁be ▁ 6 0   days ▁or ▁less , ▁with ▁bi ode grad ation ▁occurr ing ▁by ▁an a er ob ic ▁reduction ▁of ▁the ▁nit ro ▁groups . ▁The ▁half - life ▁in ▁sed iment - free ▁sea ▁water ▁was ▁estimated ▁to ▁be ▁more ▁than ▁ 1 5 0   days , ▁far ▁above ▁the ▁" very ▁persistent " ▁threshold ▁of ▁ 6 0   days . ▁The ▁ 2 0 0 8 ▁add endum ▁also ▁discussed ▁the ▁phot ol ysis ▁of ▁mus k ▁x yl ene ▁in ▁water ▁and ▁in ▁air , ▁which ▁are ▁rapid : ▁however