Landfill Leachate Toxicity Removal in Combined Treatment with Municipal Wastewater

Table 9

Toxicity of raw and treated wastewater (10% of leachate in influent I and II; the 95% confidence limit in parenthesis).

Organism	Number of tests	System	Influent		Effluent
			Average EC50 [%]	TU±SD	Average EC50 [%]	TU±SD
Daphnia magna	5	I	32 (15.2–48.8)	4.3±3.1	h.e. 28%	0.6±0.2
	5	II	23.6 (21.7–25.5)*	4.3±0.4	0 (h.e. < 10%)	0
	5	III	43.7 (38.1–49.3)	2.3±0.3	0	0
Thamnocephalus platyurus	5	I	10.6 (7.8–13.4)*	10.7±4.1	84 (76.9–91.1)*	1.1±0.2
	5	II	10.7 (9.4–12.0)*	9.4±1.1	0 (h.e. < 10%)	0
	5	III	19.8 (17.3–22.3)	5.1±0.7	0	0
Raphidocelis subcapitata	5	I	57.0 (47.5–66.5)	1.8±0.3	Growth stimulation	0
	5	II	32.3 (31.6–33.0)*	3.2±0.8		0
	5	III	55.0 (52.1–57.9)	1.8±0.1		0
Vibrio fischeri	3	I	17.1 (11.3–22.9)*	6.2±1.4	55.9 (30.7–80.3)*	1.8±0.5
	3	II	15.3 (12.2–18.4)*	6.6±1.1	87.3 (82.1–92.5)*	1.1±0.1
	3	III	30.3 (27.2–33.4)	3.3±0.3	0	0

h.e.: highest observed effect for nondiluted sample.
*Indicates significant differences versus control-III (Students 𝑡-test, 𝑃<0.05).