HENV-03

Group leaders:  work with your group to choose a toxic substance from the list below.  Research the following: 

1) Typical exposure scenarios (eg tetrachloroethylene (PCE) is commonly used in cleaning and treating fabrics)

 2) Guidance and regulatory levels for the substance (eg ATSDR, EPA, NIOSH, OSHA, all have regulatory or guidance levels for toxic substances) and describe circumstances when and how each level would be used. 

3) Typical public health concerns for this substance.    Discuss on group discussion board under “Dose Makes the Poison” 

Group leaders:   Compile your group’s research in a 1 – 2 page fact sheet under group assignments.  See guidance for Fact Sheets.

Hint – a good place to start your research:   http://www.atsdr.cdc.gov/phs/index.asp

LIST OF HAZARDOUS SUBSTANCES TO CHOOSE FROM: Formaldehyde Trichloroethylene (TCE) Tetrachloroethylene (PCE) Toluene

Cadmium Polychlorinated biphenyls (PCBs) Polycyclic Aromatic Hydrocarbons (PAHs) Vinyl Chloride

FACT SHEETS AND ACTION ALERTS

The point of a fact sheet or action alert is to get the reader to do something. More information than you need to convince them is a waste of the reader's time and risks losing their attention. Make it as easy as possible for them to take your action. If you want them to make a call, give them the number. If you want a legislator to vote yes on a bill, give him the bill number and title.

Thunder is good, thunder is impressive, but it is lightening that does the work. -- Mark Twain

· One page or two pages is best

· Make it readable - use at least 12 point font

· Keep the text brief - no one wants to read tons of information in small font that sounds all academic and boring.

· Keep the most important information in the first paragraph - what the issue is, what action is needed, and label the main message(s)

· Give references for more information – these can be at the end.

· The fact sheet must be self-contained - do not refer to previous documents or assume that they remember the information

· Use bullets and pictures when you can

· Leave lots of white space

· Make it very clear what you want them to do - Bold, text boxes, and graphics add emphasis

· Give them all the tools they need to take the action – how do I protect myself from harm?

Adapted from: http://www.cthealthpolicy.org/toolbox/tools/fact_sheets.htm

Learning Objectives:

After completing this lesson you should be able to:

· Identify/characterize various environmental hazards (chemical and physical) and their sources, pathways of exposure including vectors of transmission and kinetics and dynamics in the human/animal body.

· Describe the factors (age and psychological, nutritional, health and socioeconomic status [environmental justice] etc.) that determine human/animal susceptibility to these agents.

· Cultivate risk communication and advocacy skills in communicating environmental health

Reading Assignments:

· Chpts  6-8 in Friis

· https://www.youtube.com/watch?v=b84ghOdpKj4&index=3&list=PL0286965B6DA44BD4   

· Lead and Radon Study Guides (attached)

· AJPH 2015 Manuscript on elevated blood lead concentrations in Flint, Michigan children (attached).  Reading this manuscript is required. Group Project is extra credit (see below)  

Chemical Hazards

The video presented above gives us a glimpse into the challenging world of chemicals and environmental health.  Actually it makes my head spin. It also makes me wonder how me and my family have turned out even half way OK after years of enjoying plastic containers.  Dr.Trasande of the Children’s Environmental Health Center at Mt. Sinai Hospital alleges several health effects caused by exposure to plastics.  However, after our epidemiology lesson, you have an appreciation of how complex it is to tease out these cause-effect relationships. 

 This lesson, we will learn about the role of toxicologists, the smartest people on earth !!!.  Toxicologists are tasked with evaluating the health risks of chemicals in our environment. Toxicology requires a thorough knowledge of how hazardous substances affect the body, and at what dose you would expect increased risk.  Easier said than done!!!  It is not that simple!!!  Toxicology, especially from a public health/population perspective, can be challenging.  Most of what we know about chemicals in our environment has resulted from controlled animal experiments extrapolated to humans, or, if we’re lucky (or unlucky), actual human experiences (typically from workplace exposures).  We know relatively little about how these substances might affect the general population at low doses, never mind how they may affect unborn babies, infants, and children (as described in the video), the elderly, and other vulnerable populations.  Life is not a randomized controlled study!!!  There are many factors to take into consideration.

 Friis gives a summary of hazardous substances in Chapters 6 and 7.  This provides an overview of how chemicals in our environment represent potential risks to public health.  However, when dealing with a hazardous substance exposure, there needs to be an in depth review of its toxicology to really understand dose response.  

  Physical Hazards

Next we will focus on both ionizing and nonionizing radiation.  As Friis says, radiation is nothing more than energy that travels though space.  Sounds harmless enough!  Yet explosions and accidents with radioactive material have represented some of the most significant humanitarian and environmental crises in our history.  Certainly radioactive power can be as awesome as the “Tsar”bomb  http://www.youtube.com/watch?v=H9AMtUeyDP0  or as insidious as the tiny chronic doses received by the now infamous radium dial painters of the 1920s as described here in this amateur but excellent video:   http://www.youtube.com/watch?v=WVqbiBV07OM

Determining Risk

Exposure Pathways - Determining risk from an environmental hazard and setting regulatory standards is a complex process.  While a lay person may reasonably conclude that a site where drums leak toxic substances into an environment is not healthy, a public health professional must take a much more systematic approach.  Exposure pathway analysis is the standard method for assessing an exposure from a hazardous waste release into the environment, and toxicology is the science of determining whether that exposure poses a significant health risk.  Exposure pathways recreate the “path” the toxic substance takes from the point at which it is released to when it actually enters the cells of humans where it could cause damage.  To review, you analyze an exposure pathway by considering the following:

· Source

· Environmental Media/transport

· Exposure Point

· Exposure route

· Receptor population. 

For details or if you need further review, check out  http://www.atsdr.cdc.gov/HAC/PHAmanual/ch6.html#6.1.1  for a description of exposure pathways.

Dose-response – Investigating dose response is the next step in assessing an environmental hazard.  See Figure 3-4 in Friis for a graphical representation of the dose response.  The threshold is the point at which, above that dose, you would expect to see harmful effects and below would be harmless.  This is an important concept as we as humans in a modern society experience a barrage of exposures to multiple, potentially toxic substances.  As long as the doses are minimal and in moderation, our immune and detoxification systems in our body generally render them harmless???/minimally harmful???.  It all depends on the toxicant and the circumstances of the exposure.

So "logically", the threshold dose (i.e , that dose above which you get sick, below you are fine) of a toxic substance should be the level used to regulate hazardous substances,, right?  NOT NECESSARLY (if you are a toxicologist) or NO WAY (if you trying to limit risk to a population!!!  Environmental health is NOT that precise.  Toxicologists often use terms such as Lethal Dose 50 (LD50) to describe toxicological thresholds.  In experimentation, this is the dose at which 50% of exposed laboratory animals will die after an acute exposure   ATSDR has used the concept of Minimal Risk Levels (MRLs) as a way to regulate toxic substances, especially those for which there is likely to be chronic exposure.  MRLs are generally many magnitudes lower than toxicity thresholds to control for uncertainties such as animal vs human doses, ingestion vs inhalation, chronic vs acute, genetic variability, adults vs children, etc.  Here is more information on MRLs  http://www.atsdr.cdc.gov/mrls/index.asp  and here is a current list of MRLs posted on the ATSDR website  http://www.atsdr.cdc.gov/mrls/index.asp .  As you can see, there are a lot of holes, missing chemicals, and outdated findings.  Toxicologists have a lot of work cut out for them!

On the federal level, ATSDR’s Division of Toxicology is the unit within the Centers for Disease Control and Prevention (CDC) charged with “determining which substances should be regulated and the levels at which substances may pose a threat to human health”.  See http://www.atsdr.cdc.gov/HAC/PHAmanual/ch1.html#1.1  for a full description of ATSDR’s mandates. 

However, ATSDR is not a regulatory agency.  The Environmental Protection Agency (EPA) uses Maximum Containment Levels (MCLs) for regulating cleanup of hazardous waste sites.  They also have issued standards for common pollutants such as the National Ambient Air Quality Standards (NAAQS) as described in Friis.  The National Institute on Occupational Safety and Health (NIOSH) is the non-regulatory arm of Occupational Safety and Health Administration (OSHA), which have worked together to promulgate exposure levels for the workplace.  Different countries use different standards as well, while others follow the World Health Organization standards.  As you can see, interpreting the toxicological significance of an environmental exposure to even common pollutants can get very complicated very quickly. 

Extra Credit GROUP Study Critique. Up to 3 extra points will be available for group study critique of the attached AJPH 2015 manuscript on the elevated children blood lead concentrations in Flint, Michigan. Each group member must participate and all group members will get the same score. Use same approach as on Raz study.

Communication Toolkit: Fact Sheets

A fact sheet is a one-page document that provides basic information on a specific topic in an easy- and quick-to-read format. If the subject is just too complex to reduce to a single page, consider creating more than one fact sheet. Just make certain each fact sheet focuses on a single aspect of the overall topic.

Fact sheet are particularly useful to reporters and state and national legislators. What do all this groups have in common? Very little time to gather enough information to write a quality article or make a quality decision. Here are some things to keep in mind:

Content

· Write in lay terms, as if you are explaining it to your mother

· Find ways to simplify complex ideas. Search for comparisons and everyday analogies that will express complicated processes. Transform jargon into English.

· Write in the present tense and as active as possible

· Keep the text brief - no one wants to read tons of information in small font

· Keep the most important information in the first paragraph - what the issue is, what action is needed, and label the main message(s)

· Use terms consistently

· Double check all numbers and percents used

· If details are given in a table or chart, there is not need to give those details in the narrative (use general terms instead)

· If using lists, put them into bullets

· The fact sheet must be self-contained - do not refer to previous documents or assume that they remember the information

Layout

· One page is best

· Use at 10-14 point font

· The page should begin with the words “Fact Sheet,” followed by a very brief headline that explains the subject of the page.

· Use bullets when you can

· Leave a lot of white space

· Use bolding, text boxes, and graphics to emphasize important points

· Simple graphs and charts can give the reader the information with just a glance. Pie charts are the easiest to understand

· Give references for more information - in electronic communications you can offer links

Typical writing errors

· Identify all acronyms at first use, then use only the acronym for the rest of the document

· Example: The Center for Rural Health (CRH) was established in 1980. The CRH is based at the University of North Dakota School of Medicine and Health Sciences.

· In narrative, use the word “percent” rather than the symbol “%” Example: Of the 100 people who were sent the survey, 80 percent responded.

· Avoid use of decimals when using percents.

· Example: The population of North Dakota has increased just over one percent in the past year.

· Using numbers: In general, any number below 10 is written out as words, above 10 as numerals.

· Example: During the program, information was sent to three communities resulting in responses from 234 people.  Exceptions: When a number comes at the beginning of a sentence and dates:

· Example: Two hundred thirty-four people responded to the mailing before April

· Titles: If a title comes before the name, it is capitalized. If it comes after the name, it is not. Courtesy (non-degree) titles such as Mr. Mrs., Miss, or Ms. are generally not used and should be used only when specifically requested (and then consistently).

· Example: Center for Rural Health Director Dr. Mary Wakefield attended the meeting. Brad Gibbens, associate director of the Center for Rural Health, joined her.

· Dates: There is no comma between month and year. There is a comma between date and year.

· Example: We are planning on meeting in April 2005, possibly April 15, 2005.

· People first: When using terms to describe people, it is a good idea to use “people first language.”

· Example: Many of the children who are uninsured in North Dakota come from families with low income.

It is also a good idea to set the grammar check on your Microsoft Word program to check style also. This is done under Tools, Spelling and Grammar, Options, Grammar, Writing Style: Grammar & Style.

Copied from: http://ruralhealth.und.edu/communication/factsheets.php