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Effects on Development. Preconception (the stage is set): Intergenerational Effects Genetic Cultural Non-genetic Familial Intergenerational Effects Stress Diet Drugs, environmental chemicals. Effects on Development. Conception to pre-birth Prenatal Effects
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Effects on Development • Preconception (the stage is set): • Intergenerational Effects • Genetic • Cultural • Non-genetic Familial Intergenerational Effects • Stress • Diet • Drugs, environmental chemicals
Effects on Development • Conception to pre-birth • Prenatal Effects • Conception, zygote (0 to 2 weeks), embryo (2 weeks to 2 months), fetus (2 months to birth) • 50% of zygotes are miscarried (mother is unaware) • The zygote, embryo, and fetus are susceptible to a variety of teratogens (ionizing radiation, alcohol, drugs, hormones, chemicals, and perhaps the subtle effects of non-ionizing radiation).
These are electromagnetic waves (microwave, radio, ELF emitted from powerlines). They are ‘non ionizing’ because they do not knock out electrons from atoms. At high intensities they can heat up things (e.g., microwave ovens). At low intensities they can CAUSE BIOLOGICAL EFFECTS not by heating tissue, but instead by modifying gene expression and interfering with cellular communication. These effects Have been demonstrated to occur within intensity and frequency ‘windows’ (Electromagnetic Biology and Medicine, 25: 217–225, 2006). Non Ionizing Radiation
How safe are cell phones? Prenatal and Postnatal Exposure to Cell Phone Use and Behavioral Problems in Children Divan, Kheifets, Obel, & Olsen 2008
Behavior Problems (Epidemiology 2005, V 19, p 525) All odd ratios are adjusted for sex of child, age of mother, smoking during pregnancy, mother’s psychiatric problems, and socio-occupational level.
Neurons and glial cells (astrocytes) were exposed to non-ionizing Cell-phone radiation (GSM 800 – 1900 MHz) for 2 hours. Zhao, Zou, & Knapp (2007) Neuroscience Letters, V 412, 34-38
A is data for exposed astrocytes, B is data for exposed neurons.
Postnatal Development • Perinatal (the birth period) • Postnatal (birth to death) • Neonate (0 to 3 months, Infant (3 months to 3 years), child (3 years to puberty), adolescent (puberty to 16 or 20), adult, aged