. 2020 Jan 27;10:1229. doi: 10.1038/s41598-020-57981-0

Table 1.

Mean influent and effluent concentrations of different filter materials over experimental time.

Parameter	Unit	Influent	Effluent
Parameter	Unit	Influent	Sand	Biochar
Chemical oxygen demand (COD)	mg∙L⁻¹	305^a ± 104 (4)	116^b ± 52 (12)	69^c ± 26 (12)
Total organic carbon (TOC)	mg∙L⁻¹	93^a ± 31 (4)	50^b ± 18 (12)	34^c ± 8.8 (12)
Ammonia nitrogen (NH₄-N)	mg∙L⁻¹	42^a ± 19 (4)	40^a ± 9.6 (12)	39^a ± 9.3 (12)
Total phosphorous (P_tot)	mg∙L⁻¹	6.5^a ± 0.6 (4)	4.9^b ± 1.3 (12)	4.3^b ± 0.4 (12)
Total suspended solids (TSS)	mg∙L⁻¹	57^a ± 12 (4)	NA	NA
Electrical conductivity (EC)	µS∙cm⁻¹	1077^a ± 387 (9)	1040^a ± 402 (24)	1130^a ± 308 (24)
Turbidity	FNU	212^a ± 287 (9)	136^a ± 150 (24)	146^a ± 140 (24)
pH		7.4^a ± 0.2 (9)	7.6^a ± 0.3 (24)	7.6^a ± 0.5 (24)
E. coli	log₁₀MPN∙100 mL⁻¹	6.2^a ± 0.65 (9)	4.9^b ± 0.7 (24)	4.8^c ± 0.5 (24)
Enterococci	log₁₀MPN∙100 mL⁻¹	5.5^a ± 0.69 (9)	NA	NA

Standard deviations are presented as variation range. Letters indicate a significant difference of the mean (p < 0.05) after post-hoc analysis. Number of samples in brackets. E. coli and enterococci concentrations are given in Most Probable Number. Number of samples in brackets.