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EH730 Spring 2022 Problem Set #2 (out of 70 points) DUE: Wednesday, March 22, 2022 (6pm) 1. Examine the EJ communities in MA by navigating to the Mass.gov Environmental Justice Map Viewer on this page: https://www.mass.gov/info-details/environmental-justice-populations-in- massachusetts. (15 points total) a. Identify one town/city that has at least one block group that meets any of the Environmental Justice criteria. Describe the EJ characteristics of this block group. (2 points) Chelsea, MA is a city that has at least one block group that meets three of the Environmental Justice Criteria. This is an area that has a high minority population at 90.2%, with a median household income of $35,069, and 52.9% of households with language isolation. (Block Group 2, Census Tract 1604, Suffolk County, MA) (ESRI) b. Identify one town/city that does not meet any of the EJ criteria. (2 points) Sudbury, MA is a town that does not meet any of the EJ criteria (ESRI) c. In each of the two towns/cities you identified above, look for any active or archived Superfund sites using EPA’s Superfund Enterprise Management System database (https://cumulis.epa.gov/supercpad/cursites/srchsites.cfm). (5 points) For Chelsea there is currently one active superfund site and seven archived superfund sites (EPA, 2017). For Sudbury there were no active or archived superfund sites listed in the database (EPA, 2017) d. Summarize your findings of the above in 3 sentences or less. (6 points) Chelsea is a city that meets many of the Environmental Justice criteria, with high percentages of minorities, households with language isolation, and lower income. They also have had a total of eight superfund sites, with one currently active. Sudbury, on the other hand, does not meet any of the environmental justice criteria, and as far as the database goes, has never had a superfund site (ESRI) (EPA, 2017) (EPA, 2017). 2. In February 2021, the House Committee on Oversight and Reform released a report showing that heavy metals, including lead, arsenic, cadmium, and mercury, were measured at higher levels in baby foods. The full report is provided here. One of their conclusions was that "top baby foods are tainted with dangerous levels of inorganic arsenic, lead, cadmium, and mercury." Your assignment is to verify this conclusion, using a risk assessment framework, for inorganic arsenic. (25 points total) Specifically, conduct the following steps: (1) Hazard Identification: describe the main exposure pathway for this scenario. (2 points) The main exposure pathway for this scenario would be through ingestion of inorganic arsenic tainted baby food.

(2) Exposure Assessment: Quantify exposure point concentrations by extracting information from the Report above. Then conduct Dose calculations using supporting documentation ( hint: see Exposure Factors Handbook for average body weights, ingestion rates, etc., then calculate daily dose of arsenic). Make sure you clearly list your assumptions in sufficient detail that calculations could be reproduced. (6 points) Average inorganic arsenic in a Nurture (HappyBABY) baby food is 60ppb 60 ppb x 0.001mg/kg/ 1ppb = 0.06 mg/kg Body weight for average 6 months to <11 months = 9.2 Kg ADD = EPC * CR/BW 0.06mg/kg* (4oz/9.2kg) = 0.026 (EPA, 2022) (EPA, 2003) (3) Dose-Response Assessment: Briefly (2-3 sentences) summarize toxicity information, including available toxicity values and their relevance to the exposure you are evaluating ( hint : see USEPA IRIS database for toxicity values). Document your quantitative estimates of toxicity values that you will use. (6 points) The Oral reference dose (RfD) for inorganic arsenic is 0.0003 mg/kg-day, with a NOAEL of 0.0008 mg/kg-day and a LOAEL of 0.014 mg/kg-day. Given these are the oral doses for inorganic arsenic, it is highly relevant to the exposure of inorganic arsenic tainted baby food as the route of exposure for this issue is through ingestion, or by oral means (EPA, 2003). Oral RfD Summary NOAEL: 0.0008 mg/kg-day LOAEL: 0.014 mg/kg-day RfD: 0.0003 mg/kg-day (3) Risk Characterization: Calculate the Hazard Index for noncancer risk. (5 points) HI = ADD/RfD HI = 0.026 mg/kg-day / 0.0003 mg/kg-day = 86.67 (5) Finally, interpret the hazard index and comment on why you think this this is/is not consistent with the conclusions of this report (2-3 sentences). (6 points) The hazard index for inorganic arsenic in Nurtures (HappyBABY) food is significantly higher than one, 86.67, meaning it is very consistent with the conclusions of the report. This means there is a risk that exposure to inorganic arsenic in Nutures’ (HappyBABY) baby food will potentially lead to adverse health effects.

3. Concentrations of contaminants are often “measured” below their detection limits and recorded as “non-detect”. Explain to your neighbor, who is an artist with no science background, EXACTLY what this (non-detect) means. Your answer should be <300 words. (15 points) When testing contaminants in a sample, there is a limit to how small of an amount they can detect. Non-detect is a term used in environmental monitoring and risk assessment. It refers to the concentrations of substances below the detection limit of the machinery used to test a sample. Non- detect data is reported as less than the detection limit (<), followed by the limit. Non-detect does not mean the substance is absent from the sample, only that the equipment used to test it cannot. If the sample is less than the detection level or a non-detect, it is so small that it is not a concern. For example, if a scientist were to test water for the presence of a chemical and the detection limit for that chemical is 0.05 ppm, any concentration of that chemical below 0.05 ppm would be considered non-detect, meaning the equipment that was used to test the water could not detect any of the chemicals in the sample. It identifies and mitigates risks to human health and the environment. 4. You just received a dataset on PFAS in drinking water. Some of the concentrations reported from the lab are listed as non-detects. To analyze these data, you choose to replace your non-detect values with a value: ½ the detection limit. Explain to your neighbor why you are doing this and how this will affect the mean or median concentrations of the samples. Your answer should be <300 words. (15 points) Non-detects are values below the detection limit, meaning they cannot be accurately included in the data set as they are. Replacing my non-detect values with a value of ½ detection limit would allow for a complete analysis, specifically to approximate the amount of PFAS present in the sample or, in other words, to gain insight into the overall contamination levels of the water sample. Instead of having some values listed as “non-detect,” they would have a value of ½ the detection limit alongside the various other data. This decision would lead to slightly higher mean or median concentrations. Environmental Protection Agency. (2003). Arsenic, inorganic; CASRN 7440-38-2 . EPA. https://cfpub.epa.gov/ncea/iris/search/index.cfm Environmental Protection Agency. (2017, October 20). Search superfund site information . EPA. https://cumulis.epa.gov/supercpad/cursites/srchrslt.cfm?start=1 Environmental Protection Agency. (2017, October 20). Search superfund site information . EPA. https://cumulis.epa.gov/supercpad/cursites/srchrslt.cfm?start=1 Environmental Protection Agency. (2017, October 20). Search superfund site information . EPA. https://cumulis.epa.gov/supercpad/cursites/srchrslt.cfm?start=1

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Environmental Protection Agency. (2022, March 21). Exposure factors handbook 2011 edition (final report) . EPA. https://cfpub.epa.gov/ncea/risk/recordisplay.cfm? deid=236252 ESRI. (n.d.). Massachusetts 2020 Environmental Justice Populations . Mass-eoeea.maps. https://mass-eoeea.maps.arcgis.com/apps/webappviewer/index.html? id=1d6f63e7762a48e5930de84ed4849212

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