A Survey has been developed to document and compare GIS utilization in the workplace. This survey assesses GIS availability and utilization in both academic and non-academic work settings. The purpose is to document the need for GIS experience as an occupational skill. GIS is currently being underutilized by most companies. Spatial Technician and Analyst activities and a few managerial activities requiring GIS are reviewed.
This survey, which takes about 20-25 mins to complete (’tis a bit long), can be accessed at
GEOGRAPHIC INFORMATION SYSTEMS – Part 2
[Note: The full report filed for the grant-funded portion of this work appears in this site at:
The main project to present as an example of environmental public health GIS is the study I engaged in from summer of 2001 to present on the effects of chemical release for the state of Oregon on local population health related features. In particular this study focused on several cancer types and a review of chemical exposures often considered to be the causes for such problems as lung cancer (halogenic and small aromatic organic compounds, or heavy polycyclic aromatics), ovarian and breast cancer (organic chemicals with polycyclic (multi-ring) structures enabling them to behave much like steroid hormones and interact with specific hormone/steroid receptors), testicular cancer (ditto), skin cancer (various compounds), bone marrow and white blood cell-related cancers (esp. various forms of leukemia, along with hodgkins and non-hodgkin’s lymphoma), and possibly various forms of oropharyngeal and gastrointestinal forms of cancer (high MW anthracene-derivatives and quinone/tannin-derivatives).
This research required that several analyses be done of the State of Oregon in which state and federal data on chemical release sites were compared with known cancer cases. These analysis first took place at fairly broad area levels, namely a series of aerial evaluations of cancer rates at the county and regional demographic level. Next, census block data was evaluated to determine how the state should be divided into specific and fairly well-isolated geographic regions. Finally, the case histories were reviewed and point maps developed for use in the development of an isopleth or contour map depicting cancer incidence in relation to space, without standardizing this information in relation to standardized (age-gender corrected) demographic data.
Because the focus of this research project is on the chemical release sites, not the cancer cases, the goal here is to carry out a form of spatial analysis involving cancer incidence that does not use the typical epidemiologic routes of analysis. The main requirement for these different cancer regions in Oregon was that they demonstrate a certain amount of geographic separation, in order to review each region separately from its neighbors. In order to be isolated or detached from nearby neighbors, there had to be a limited number of roadways connecting one region to the next. This was done in order to reduce the likelihood that significant amounts of travel between neghboring regions would take place. In some cases, obvious landforms prevent or slowed down these easy access routes from one region to the next. In other cases, too many of these routes existed, requiring that some regions be isolated first based on major urban-related factors and secondly on distance and presumed time of travel between home and potential worksites.
After attempts were made to break down the census blocks- and block group-defined boundaries into specific natural breaks between populated areas, the following regions of the state were developed. Note, due to significant population densities along the Willamette Valley traveling from north to south in western central Oregon, this region was broken down roughly into regions in which a central urban setting could be defined as its primary center for urban density (i.e. Eugene, Salem, Portland), with satellite urban areas noted to exist within these boundaries which had the potential for residents to access other major urban-defined regions as well. (To study these north-south bordered regions, two other were used, the first allowed for data overlaps to occur between different population groups and chemical exposure sites, the second (focused on Portland) assumed Portland to be the main urban setting and adhered closely to the urban boundaries politically defined by the various local governments.
Chemical Release Analysis and Cancer
Chemical Release Sites can be broken down numerous ways into categories, which in turn are used to define the degree of sophistication researchers wish to engage in with their GIS research project on chemical releases. The most common methods of identifying sites for research typically involved reported case data, eitehr through local hearsay or by way of county-related research projects involving particular chemical cases. When a series of cases are reported or publicized, thereby creating or increasing the suspicion for one or more local release sites as a possible cause, the type of research these claims can often lead to are rightfully considered highly biased in many cases–in crude terms, the researchers (and public sponsoring such research) are really just looking at some industry or place to point the finger at, a relic of the old Love Canal history of environmental pollution research and studies.
Fortunately, most research employed by epidemiologists pretty much prevent these prejudgments from happening. However, the problem with epidemiological research is it is typically hindered by the limits of the data that are provided. We most often rely upon block or areal data in order to improve the chances for anonymity on behalf of the victims whose changes in health led to this research in the first place. This use of areal data does hinder the mathematical power of such studies due in part to the error introduced by these methods. In GIS, there are some methods proposed that reduce the high value placed on demographic data utilization to study areas. We can use census data, and apply it using a house-by-house or building-by-building, relying upon some rather sophisticated calculations designed to produce such outcomes using aerial photography and remote sensing data.
The studies I tend to engage in pay heed to census data, and use it whenever necessary, but also rely more upon the site data instead of people data in order to draw my conclusions. As you will see by reviewing these methods, some of the methods tested here have considerable power when evaluated in combination with other spatial population data forms, including the use of the Gini Coefficient used to measure local poverty, or the use of any opf several aerial economic calculations methods is use by demographers and economists. For now, I will stick to the sites and their chemistry to make most of my spatial analyses points with regard to chemical release sites mapping.
Chemical release is very much the focus of most of my studies in cancer epidemiology GIS. This is due in part to my twenty years of experience as a lecturer/adjunct professor in chemistry, toxicology, phytoecology and phytochemistry, environmental chemistry, disease ecology, and GIS-Remote Sensing.
Since 1987, Oregon has had more than 25,000 sites either reported and considered for review for their potential toxicity. Many of these were immediately removed from the list of toxic sites due to non-confirmational environmental chemical evidence following field visits. Many sites remain on any of several lists due to the need for clean-up. Less than 5% of those sites are under current or consideration for superfund site clean-up, and/or are included in the pending lists of sites due for environmental clean-up.
In addition, since 1987, Oregon has had many of its sites removed from toxic site listings, and many others reviewed in any of several ways. During the first phase of this release site research project in fact (the first 2 years), first the superfund sites were mapped, followed by the mapping of 82 other sites considered for superfund funding but not yet included on the superfund list. In addition, of the thousands of chemical release sites with suspected exposure risks to the public, approximately 450 were classified as “Confirmed Release Inventory Sites” (CRIs), meaning a certain amount of confirmation was made regarding the reported chemical spill and land use history. Each of these 450 sites was then evaluated independently and their chemical spills reports data pulled from the Oregon State University database on these sites, which was then analyzed in numerous ways and finally these results mapped. During the subsequent phases of this development of the database on all of the remaining Oregon ECSI or TRI sites, site information was gathered a small percentage at a time, and databases developed and then used to produce the first maps on this information. Anywhere from two to three thousand sites, most recently reported or very small in size or amounts of chemicals released, still have to be mapped.
In a recent review, database update, and mapping of 670 of the first 1000 sites placed in the ECSI/TRI report during the first two years approximately, most these sites contained chemical data but were not in the CRI listing in spite of their considerable age on the list. Reasons for their exclusion were interesting (politically that is). Two counties had little chemical data filed at all for many of their sites This may have been due to the fairly rural nature of these counties, since due to their location and limited revenues it was presumed that both were simultaneously by the same environmental recovery program or agency, with actions that may have not been initated at the time of this research. Other times, the causes for exclusion from sueprfund review were obvious. Some sites lacked chemical information and/or filed the required papers for superfund review fairly late. This was the case for at least one of the most toxic sites in the state, in need of but not eligible for superfund funding needed to clean-up its suburban setting. By missing such deadlines for superfund clean-up consideration, these outcome delayed the cleanup process for several more years.
As time passed over the years while carrying out this project, I noted that with time, the percentage of CRIs in the remaining site lists decreased as the number of new TRI sites increased. In general, the overall severity of all sites combined has decreased with time, making the seriousness of these sites less a public health concern, at least at the sueprfund level. For now, the CRIs and portions of the ECSIs/TRIs documents in the state and federal databases remain the focus of this study.
The sites described at the Oregon data storage facility provide the best details for reviewing these sites, although not in any easily downloadable form. The fairly complete reports filed for most of these sites contrasts greatly with similar datasets received from otehr region warehouses in the midwest. The Oregon reports provide the best information related to TRIs, on a per site, per chemical report basis. This method of guessing a site’s chemical release history I have termed “chemical fingerprinting.” The data used to develop this work has therefore enabled me to develop a way of catagorizing these sites based on their chemical profiles. This fingerprinting of a site is covered extensively later in this work, and is based primarily on my review of approximately 450 to 550 sites (depending on sites being referred to). As some of my much later research shows, this method is fairly reliable for use in identifying chemical indicators that are strongly related to just certain site types or classes (these are also reviewed separately due to the methods used to reclass chemical release sites for such a review). And I am not the first person to try and document the chemical characteristics of sites based on their landuse and industrial and manufacturing history. My method does differ though from earlier attempts in that I used a reclassification method previously not considered, in which both chemical groups and toxicity/carcinogenicity were taken into consideration along with a site’s SIC data and the need for reclassifying that SIC to more appropriately group chemically-related sites together for more extensive reviews.
To date, more than 45,000 chemical spill reports have been reviewed and added to the database, and are used to produce many of the isoline maps you will see.
The following map depicts the distribution of TRI sites statewide in relationship to the major urban regions defined in the 1990 and 2000 census. This analysis was done using just a portion of the state data obtained from a national information source, and so only includes the active TRI sites included on the source’s database. Notice the tendency for reporting to be most significant in heavily populated regions, due in part to increased public awareness of this important environmental issue, and perhaps due to the strong impacts of local political groups and non-profit organizations devoted to the environmental cause, with their main offices and funding sources somehow affiliated with the Portland urban and university settings.
The Application of Theissen Polygons
By mapping this site-related information, we are for the most part only modeling the chemical release history for the state, especially when we map all tests performed regardless of outome. In one analysis performed early on, several sites were found to be above the defined “safe levels” for several compounds. These were reviewed in the following map, in which a Theissen Polygon producing extension for ArcView was also employed to test its applicability to this type of research project. This use of the Theissen Polygon method for areal analysis is one of the first natural outcomes of GIS projects developed for intense statistical evaluation and population health review. For this reason, a large amount of time was spent during the next several years analysing this data with the use of various forms of spatial statistical tool and calculators in mind. These projects are presented in another section of this site.
The chemical release histories of 72 superfund applicant and 10 superfund sites in Oregon.
The chemical release histories and types of chemicals released at 450 Confirmed Release Inventory sites in Oregon.
Identification of the 22 most toxic chemical release sites in the state of Oregon based on an evaluation of the chemical release histories for non-superfund applicant, non-superfund sites.
The use of Theissen Polygons in analyzing toxic release site chemical information in relation to risk for human exposure. Major release sites situated close to the Columbia River from the Umatilla region to Astoria, Oregon.
The development of three formulas or algorithms used to define long term risk values assigned to each site based on standard chemical profile patterns applied to toxic release sites.
The spatial relationship between SIC-defined sites and 2500+ Oregon leukemia-lymphoma cases.