– Reproductive Health and Lead
By Elizabeth O'Brien, BSc, Grad Dip in
Educational Studies (Health Educ’n), Manager, Global Lead Advice & Support
Service (GLASS) run by The LEAD Group Inc. Australia
The Hertz-Picciotto 2000 (see below)
article about miscarriage concludes that “lead exposures in the range of 10-25
µg/dL could have adverse effects on pregnancy” and “the odds ratio for
spontaneous abortion was 1.8 (95% confidence interval 1.1-3.1) for every 5 µg/dL
increase in blood lead”.
Another Mexican lead and miscarriage
study found that “Maternal blood lead levels during the first 12 weeks of
gestation were associated with spontaneous abortion.” (Borja-Aburto 1999)
Our volunteer researcher Robert Taylor
is going to start on an article about mothers passing lead to their unborn
babies, after he completes another article he’s researching (on leaded
aviation fuel) and since he has written “Fact Sheet: Alcohol’s link to
higher lead and iron levels” at Alcohol_link_to_higher_lead_and_iron_levels_20110831.pdf
Sheet: Cigarette Smoking & Lead
Toxicity” at Taylor_Cigarette_Smoking_and_Lead_20101005.pdf.
The National Toxicology Program (NTP),
US Department of Health and Human Services (DHHS) has published a NTP
MONOGRAPH ON HEALTH EFFECTS OF LOW-LEVEL LEAD June 13, 2012
including: APPENDIX E: HUMAN
STUDIES OF REPRODUCTIVE AND DEVELOPMENTAL EFFECTS OF LEAD CONSIDERED IN DEVELOPING CONCLUSIONS.
Health Effects of Low-level Lead Evaluation
- NTP Monograph on Health Effects of Low-level Lead (June 2012)
It’s a crying shame that all these
topics are not part of medical training or Continuing Medical Education, and the
health department don’t seem to make any effort to educate doctors about lead
and reproductive effects or lead exposure in general.
No Australian state health department
has ever to my knowledge had a policy on the target blood lead level to be
reached prior to attempting conception or during the pregnancy.
Until a state or national Australian
policy can be developed, a very useful document from the US is: "Medical
Management Guidelines for Lead-Exposed Adults" at www.aoec.org/documents/positions/MMG_FINAL.pdf
You will see that on page 8 of the US
Guidelines, the target blood lead level (BLL) for a woman (and presumably also
for a man) wishing to conceive is given as 0.24 micromoles per litre (µmol/L)
which is equivalent to 5 micrograms per decilitre (5 µg/dL):
"Because fetal blood contains
approximately 80% of the blood lead concentration of the mother, and because of
the risk of spontaneous abortion, the panel’s recommendation is that the
mother’s BLL should be kept below 5 µg/dL (0.24 µmol/L) from the time of
conception through pregnancy."
The US Guidelines have other useful
recommendations and are well worth a read by a couple wishing to conceive or
already pregnant, and by their doctors.
It is my understanding that Medicare
will cover the cost of up to 4 blood lead tests in any 6 month period so if you
have a result which exceeds the target blood lead level, you can have the first
retest as soon as lead sources have been eradicated and nutrition attended to,
then you will know how close you are to the target blood lead level.
Calcium, iron and zinc are recommended
for couples wishing to conceive and for pregnant women although the doctor would
likely want to order iron studies before recommending an iron supplement. See
the articles in our Nutrition Info Pack (following) for further details.
The components of our Info Pack 6 on
Reproductive Health and Lead which are available in electronic format are as
www.lead.org.au/lanv4n3/lanv4n3-13.html - This article is
useful but it states: "Both partners should aim to have their blood lead
levels below normal (readings of 5 micrograms per decilitre (5 µg/dL) or 0.24
micromoles per litre (0.24 µmol/L)) prior to conception" and no study has
been done in Australia indicating what exactly "normal levels" are. In
the USA, the most recent in a series of large-scale national blood lead surveys
found a geometric mean blood lead level for women aged between 20 and 59 of 1.7
micrograms per decilitre and for men in the same age range, the mean was 2.9 µg/dL.
[Reference: Table 2 in "Blood Lead Levels --- United States, 1999--2002 [NHANES
IV] at www.cdc.gov/mmwr/preview/mmwrhtml/mm5420a5.htm
- "Lead and pregnancy" published in Lead Action News LANV5N3 p 5. www.lead.org.au/lanv6n2/update005.html - "Pregnant or
Planning a Pregnancy?"
www.lead.org.au/lanv6n2/update002.html - "Breastfeeding
And Lead - What do Mothers Need to Know?"
"Declining Sexual Health - a
victim of modern day diets and lifestyles" by Janette Roberts [The
Foresight Association, Australian Branch, AND Balmain Wellness Centre], at http://www.articleslog.com/2008/01/16/90764-declining-sexual-health--a-victim-of-modern-day-diets-and-lifestyles.html
"Preconception Care: What can our
preconception plan do for you?" by Lane Cove Wellness Centre, at http://www.naturaltherapypages.com.au/connect/wellnesscentre/preconception_care/lane_cove_wellness_centre_pharmacy_preconception_care
“The evidence that lead increases the
risk for spontaneous abortion” by Irva Hertz-Picciotto, published in AMERICAN
JOURNAL OF INDUSTRIAL MEDICINE 38:300±309 (2000), AVAILABLE FOR PURCHASE AT http://onlinelibrary.wiley.com/doi/10.1002/1097-0274(200009)38:3%3C300::AID-AJIM9%3E3.0.CO;2-C/abstract