Aliran Sungai Roomo telah tercemar oleh bahan-bahan organik terutama dari limbah domestik dan industri.Cemaran logam berat juga dipastikan ada dalam sungai tersebut.Logam berat ini masuk ke dalam sedimen dan biota yang hidup di lingkungan tersebut dan dapat terakumulasi pada seluruh bagian tubuhnya.Tujuan penelitian ini adalah untuk menentukan tingkat pencemaran logam Pb, Cd, dan Cu dalam air dan sedimen Sungai Roomo Gresik serta menganalisis biovailabilitas logam berat tersebut.Metode ekstraksi bertahap dan digesti basah digunakan untuk melakukan spesiasi dan ekstraksi logam dari sedimen serta konsentrasi logamnya diukur menggunakan Spektrofotometer Serapan Atom (AAS). Kandungan logam Pb, Cd, dan Cu dalam aliran sungai Roomo Gresik telah melebihi batas yang diperbolehkan, yaitu  berturut-turut 1,6038-7,8365 mg/L; 0,0251–0,0798 mg/L; dan 0,1709–0,2249 mg/L dalam air dan 213,7750–539,0763 mg/kg; 3,3467–39,7071 mg/kg; dan 36,9168-190,7079 mg/kg dalam sedimen. Pola spesiasi logam berat tersebut sebagai F1 atau fraksi EFLE (easily, freely, leachable, exchangeable), F2 (reducible), F3 (oxidisable), dan F4 (resistant) adalah sebagai berikut: F4 > F2 > F1 > F3 untuk Pb dan Cd, sedangkan Cu dengan pola F3 > F4 > F2 > F1. Logam Pb, Cd, dan Cu yang bioavailable berturut-turut 2,78-7,11%, 1,98-20,44%, dan 2,48-13,66%, sementara yang berpotensi bioavailable berturut-turut 10,05-16,81%; 9,41-54,44%; dan 15,18-94,19%. Logam Pb, Cd, dan Cu yang non bioavailable berturut-turut 79,53-84,22%, 25,11-86,04%, dan 1,84-80,67%. Dengan demikian, Sungai Roomo Gresik telah tergolong sebagai sungai yang tercemar. Kata kunci: biavailabilitas, logam berat, sedimen, spesiasi, sungai The Roomo River Stream has been polluted by organic materials which were mainly from domestic and industrial waste. Heavy metals were also ensured contaminated the river. These heavy metals enter sediments and can accumulate in the biota living in the river. This study was aimed to determine the level of pollution of Pb, Cd, and Cu metals in the water and sediments of the Roomo Gresik River and to analyze the biovability of these heavy metals. The sequential extraction and wet digestion method were used to perform a speciation and extraction of the metals from sediments. The concentration of the metals was measured by the use of Atomic Absorption Spectrophotometer (AAS). The contents of Pb, Cd, and Cu metals in the river were exceeded the allowed limit, which were 1.6038-7.8365 mg/L; 0.0251-0.0798 mg/L; and 0.1709-0.2249 mg/L, respectively in water and 213.7750-539763 mg/kg; 3.3467–39.7071 mg/kg; and 36.9168-190.7079 mg/kg, respectively in sediments. The pattern of heavy metal speciations as F1 or EFLE fraction (easily, freely, leachable, exchangeable), F2 (reducible), F3 (oxidizable), and F4 (resistant) were as follows: F4>F2>F1>F3 for Pb and Cd, whereas Cu with the pattern of F3>F4>F2>F1. The percentages of bioavailability of Pb, Cd, and Cu metals including readily biavailable were 2.78-7.11%, 1.98-20.44%, and 2.48-13.66%, potentially bioavailable were 10.05-16.81%, 9.41-54.44%, and 15.18-94.19%. Non-bioavailable were 79.53-84.22%, 25.11-86.04% and 1.84-80.67%, respectively. Therefore, the Roomo Gresik River has been classified as a polluted river. Keywords: bioavailability, heavy metals, river, sediment, speciation

Penelitian mengenai distribusi logam berat Pb dan Cu dalam air laut, sedimen, dan rumput laut di perairan Pantai Pandawa telah dilakukan. Penelitian ini bertujuan untuk mengetahui kandungan total logam berat Pb dan Cu serta distribusinya di perairan Pantai Pandawa. Preparasi pada sampel sedimen dan rumput laut menggunakan metode digesti dengan larutan reverse aqua regia dengan bantuan ultrasonic bath pada suhu 60oC selama 45 menit dan dipanaskan dengan hot plate pada suhu 140oC selama 45 menit. Analisis logam berat Pb dan Cu menggunakan spektrofotometri serapan atom. Hasil analisis terhadap logam berat Pb menunjukan distribusi logam berat Pb dalam air laut, sedimen, dan rumput laut dari masing-masing lokasi pengambilan sampel di perairan Pantai Pandawa berkisar antara 0,8479 sampai 1,9070 mg/L untuk air laut; 17,0833  sampai 76,25 mg/kg untuk sedimen; dan 13,2749 sampai 51,3252 mg/kg untuk rumput laut. Hasil analisis terhadap logam berat Cu menunjukan distribusi logam berat Cu dalam air laut, sedimen, dan rumput laut dari masing-masing lokasi pengambilan sampel di perairan Pantai Pandawa berkisar 0,0015 sampai 0,0054 mg/L untuk air laut; 0,6699 sampai 1,4554 mg/kg untuk sedimen; dan 0,0623  sampai 0,2233 mg/kg untuk rumput laut.  penyebaran dari logam berat Pb dan Cu di perairan Pantai Pandawa menujukan kandungan logam berat Pb dan Cu lebih banyak berada pada sedimen dari pada air laut dan rumput laut. Logam berat Pb dan Cu cenderung terdistribusi lebih banyak pada lokasi yang memiliki intensitas aktivitas yang lebih banyak di perairan Pantai Pandawa.

Bedugul area is a vegetable producing center in Bali that also develops organic farming. This study aimed to determine the bioavailability of Pb and Cu in an organic farm in Bedugul and the content of both metals in broccoli before planting and at harvest. Metal extraction was carried out through wet digestion and its bioavailability was determined by the application of the sequential extraction methods. The measurement of the two metals was accomplished by using AAS. The total Pb content in the organic soils before and after harvesting were found to be 746.102-897.3754 mg/kg and 277.778-328.88217 mg/kg, while Cu were of  93.1212-11-114.3259 mg/kg, and 48,608-92.3708 mg/kg, respectively. The bioavailability of Pb and Cu in soils before planting was different from that of at harvest. Pb metal in organic soil before planting which were readily bioavailable, bioavailable, and nonbioavailable were were found to be (17.80-21.62)%, (44.07-47.65)%, and (30.73-36, 89 )%, while Cu were of (5.02-7.89)%, (55.73-60.57)%, and (32.81-39.25)%, respectively. The total Pb and Cu contents in broccoli were of (27,2968-30,3621) mg/kg and (27,0303-30,0223) mg/kg, respectively. Keywords: bioavailability, broccoli, organic agriculture soil, Pb and Cu, speciation

A study about speciation and bioavailability of heavy metals Pb and Cu in strawberry fruits and in the strawberry soils in Bedugul areas has been carried out. This study was aimed to determine the concentrations of Pb and Cu in the fruits and the soils, as well as speciation and bioavailabilities of both metals in the soils. Wet digestion method with reverse aqua regia was applied for determining the total metals, while sequential extraction method was performed to fractionate the metals bound to the various phases of the soils. The measurement of both metals was carried out by the use of AAS (Shimadzu, AA-7000). The total Pb and Cu contents in the fruits were 2.5903-9.2019 and 0.8744-1.1567 mg/kg, respectively while in the soils were 20,7912 -39.0144 and 39.3154-42,6620 mg/kg, respectively.  In the speciation of both metals in soils, it was found that Pb and Cu associated with EFLE phases were 3.4944 and 1.2454 mg/kg, respectively, while those bound to Fe/Mn Oxides phases were 5.6652 and 3.1860 mg/kg, respectively. The Pb and Cu bound to organic/sulfide phases were 7.9553 and 5.5913 mg/kg, respectively and those bound to resistant phases were 13.4471 and 31.0796 mg/kg, respectively. Bioavailabilities of Pb and Cu in the soils were dominated by non bioavailable fractions, i.e. 43.69 and 76.11%, respectively, followed by the fractions of potentially bioavailable, and the lowest fractions were found as readily bioavailable.

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