ABSTRACT
The purpose of this Investigatory project is to determine the effect of different substrates
on the biodegradability of SM plastic bags. The materials needed are: 6, 1-litre glass jars; 6,
7”x9” aluminums trays; 12 pcs. 3”x4” SM plastic bags; 500g loam soil; 500g compost soil;
500mL seawater; 500mL tap water; Analytical balance; Graduated cylinder; and Weighing scale.
The procedure involved cutting the SM plastics bags into 3”x4” sizes strips. Label the strips into
C1, C2, C3 for compost soil, L1, L2, L3 for loam soil, S1, S2, S3 for seawater and T1, T2, T3 for
Tap water treatments. Then determine the initial weights of the plastic strips in grams using the
Analytical balance and then record in a logbook. Three aluminum trays (7”x9”) were labeled C1,
C2, and C3. Five hundred grams of compost soil were measured using a weighing scale and
placed in each tray. Another three aluminum trays (7”x9”) were labeled L1, L2 and L3. Five
hundred grams of loam soil were placed in 3 each tray. One hundred mL of tap water were
mixed with the soils. Plastic strips labeled C1, C2 and C3 were placed in trays labeled C1, C2
and C3 containing compost soils. Plastic strips L1, L2 and L3 were placed in trays L1, L2 and L3
containing loam soils. Five hundred mL of seawater were placed each in three glass jars. The
jars were labeledS1, S2 and S3. In another three jars, 500mL of tap water were placed. The jars
were labeled T1, T2 and T3. Plastic strips labeled S1, S2 and S3 were placed in jars containing
seawater while plastic strips T1, T2 and T3 were placed in jars containing tap water.
Based on the data gathered from the TABLE 1- Percent weight loss in SM plastic strips
exposed to different substrates after 68 days exposure period, the results are the following: DFFERENT SUBSTRATE MEAN
a. Compost Soil 18.28
b. Loam Soil 8.70
c. Tap water 3.80
d. Salt water 19.74
TOTAL: 12.63