Chapter 18. Chemistry Lessons

WHITNEY

On the drive home, I pondered not only what Macy had told me, but how she'd chosen to deliver the message. Though she hadn't asked Buck and me to keep mum about the autopsy results, it had certainly seemed like she'd intentionally left Gideon out of the conversation. Why? Even though the seafood had been cleared as the source of Joanna's poison, did Macy nonetheless think something Gideon had done might have brought about her mother's death? Was there some other reason? Or had I simply misinterpreted things, and she hadn't meant to be dismissive at all? She'd left Lane out of the conversation, too. Hmm…

I also considered how Joanna might have ingested mercury in a way that only she could be affected and not others. Might she have attempted to take her temperature when she'd been suffering the intense headache, and somehow inadvertently swallowed the mercury when the thermometer broke? It seemed she'd have been aware if that had happened, though. Maybe there'd simply been a small crack in the thermometer and some mercury had oozed out, and she hadn't realized it.

Curious, I made a detour to my parents' house. As an ear, nose, and throat specialist, my father probably didn't have an in-depth knowledge of poisons. Still, he'd done rotations back when he'd been in med school, and surely had learned some things about poisons then. He also golfed with his doctor buddies and might have heard things.

As I walked in the door, Yin-Yang skittered over to say hello. As before, I greeted the dog with a kiss on the head.

My parents looked up from the couch, where they'd been watching a legal drama.

My father stood and came over to give me a hug. My mother, who'd seen me just the day before, merely sat up on the couch. She grabbed the remote and tapped the button to pause their show. "Hey, hon. I didn't realize you were planning to stop by."

"I didn't, either," I said. "Not until a few minutes ago, anyway."

She ran her eyes over my dark, demure outfit. "Where have you been?"

"Memorial service for the woman who died at the fire station." I plopped down in an oversized chair and put my feet up on the ottoman. I turned to my father, who'd retaken his seat next to my mother on the couch. "What do you know about mercury poisoning, Dad?"

"Enough to fill a thimble," he replied.

"That might be all I need." I told him about Joanna, her symptoms, and what Macy had told me tonight. That she'd been poisoned by elemental mercury, not methylmercury. "I'm wondering if she might have tried to take her temperature when she had the bad headache the day she went to urgent care, or maybe if she tried after, before she came to the fire station. What would happen if the thermometer had broken on her and she swallowed the mercury?"

Dad sat up, looking thoughtful. "For starters, most people use digital infrared thermometers these days, not oral thermometers. Secondly, most oral thermometers these days don't contain mercury."

"They don't?"

"No. The old-fashioned mercury thermometers had a silver line, because that's the color of mercury. Today's oral thermometers generally contain alcohol, either ethanol or isopropanol. Red dye is added to make the temperature easier to read. The volume of the liquid changes with temperature, and that's how you get the reading. Heat makes the liquid expand."

Though he had a point in offering this information, he still hadn't answered my question. "But what if someone had an old mercury thermometer and happened to swallow the mercury? Would they get sick, or maybe even die?"

To my surprise, my dad said, "No. Swallowing mercury from a broken thermometer was actually a somewhat common occurrence back in the day, especially for children. Swallowing mercury poses virtually no health risk because it's not readily absorbed as it passes through the digestive system. Not by a healthy person, anyway. Ingesting mercury only poses a risk if someone has an unhealthy digestive system, such as someone who suffers from ulcerative colitis."

Did Joanna have a digestive issue?I had no idea. It wasn't exactly the type of thing normally discussed in polite company. "What if you touch mercury? Can it be absorbed through the skin and hurt you?"

"It would be unlikely," Dad said. "Only minute amounts are absorbed through healthy skin. But handling it could pose a health risk to those with a skin condition, such as psoriasis."

Had Joanna had such a condition?If such were the case, it seemed Macy might have mentioned it while we were talking earlier. I didn't recall noticing any lesions or patches on Joanna's skin.

My father went on. "You've heard the term mad as a hatter, haven't you?"

"Sure." I'd read Alice in Wonderland and Through the Looking Glass as a child—seen the Disney movie, too. The Mad Hatter had been an entertaining, though admittedly creepy, character. "What about it?"

"The reason hatters went mad was because they used a form of mercury to cure the felt they used to make their hats. When the mercury was heated, it released vapors that eventually affected their brains. Inhaling mercury is one of the ways it enters the body." My father picked up Yin-Yang and set her on the couch between him and my mother. "People are often exposed to poisons in their jobs. Where did the woman work?"

"She was retired," I said. "I'm not sure for how long, but judging from her age I'd guess two or three years. But she worked in manufacturing years ago."

"What kind of manufacturing?"

"I don't know."

"Places are much safer now than they used to be," Dad said. "People got exposed to all sorts of things decades ago, before the Occupational Safety and Health Administration was created. Sometimes they still do. OSHA imposes fines on companies when they find violations, but some CEOs just chalk up the penalties to the cost of doing business and don't make costly changes to ensure their workers' safety. Just look at the coal industry. Nearly every time there's a disaster, it turns out the coal company had received a series of citations but hadn't changed their practices."

I asked my father if checking for mercury poisoning was routine for someone suffering from headaches and dizziness.

"It definitely wouldn't be included in a routine preliminary test," he said. "If the symptoms persisted, a physician might eventually test for it, but there'd be any number of more common potential causes the doctor would want to rule out first."

My father went on to compare the practice of medicine to automotive repair. If the cause of a health problem wasn't immediately obvious, the doctors and mechanics had to troubleshoot, starting with the more likely causes and working their way forward step by step. It would be costly both in money and time to perform every diagnostic procedure right away. The potential causes were ruled out one by one.

In other words, it seemed that the doctor Joanna had seen at urgent care had likely followed standard protocols, and Macy might not have a case for malpractice against him. I wasn't sure how to feel. I was glad that I might not be dragged into an ugly lawsuit, but I felt terrible for Macy. It would be hard to know that the source of her mother's health problem could have been easily ascertained had the right test only been given and the correct lifesaving procedures administered.

I thanked my dad for the information and stood to go.

"Is that all you wanted from me?" my dad said, putting a hand over his heart as if I'd broken it. "Just some boring medical information?"

"Of course not," I replied. "I want a hug, too, before I go."

He gave me the hug and walked me to the door. My mother came with him and hugged me as well. I felt lucky to still have both of my parents. Macy was only a few years older than me, and she'd already lost both of hers.

When I arrived home, Sawdust and Cleo scampered to the door to greet me. I reached down to give each of them a scratch behind the ears.

Emmalee sat on a stool at the breakfast bar in the kitchen, poring over a college textbook. Her laptop sat next to it, along with a steaming mug of fresh coffee. She tossed a "hey" my way. Deep worry lines puckered the skin between her brows.

The cats followed me as I walked to the kitchen. "Cramming for your final?"

"Yes," she said on a sigh. "I don't know what I was thinking taking a summer class, especially history. Seems like we cover an entire century every day." She put her hands to her head, grabbing fistfuls of red hair in angst. "Argh! How am I supposed to remember all these dates and names and places?"

"You got this, Emmalee. You've memorized all the recipes for the café menu, right? That's a lot of details to remember."

My affirmation seemed to work. She lowered her hands and sat up straighter. The worry lines disappeared, too. "True. If I can remember to put a quarter teaspoon of onion powder in our slaw seasoning, I can remember that John Brown's raid took place in Harpers Ferry." She took a slug of coffee. "How was the memorial service?"

I gave her a rundown. Samira's accusation that Buck and I were money-grubbers. The two Bottiglieri siblings who'd accosted us. The tense interaction between Macy and Lane. Macy's revelation that her mother had, in fact, died of mercury poisoning.

"Mercury?" Emmalee tapped her pen against her lips, thinking. "Where did it come from?"

"We don't know the source," I said. "At least, not yet." I hoped to come up with some ideas tonight.

After feeding the cats a handful of treats, I left Emmalee to her studies and went to my bedroom, where I kicked off the ballet-slipper flats and shed the simple black dress I'd worn to Joanna's memorial service. I rid myself of my bra, as well, and changed into a pair of comfy pajamas. Grabbing my laptop, I curled up on the sofa—a cat on each side of me—to do some studying of my own.

I logged on to peruse the worldwide web for more information about mercury. First, I searched for oral fever thermometers. Though the recommended models on various websites contained alcohol rather than mercury, oral thermometers containing mercury were still readily available, probably because the amount contained therein was small enough as to pose only minor risks to otherwise healthy people if swallowed. A typical mercury fever thermometer appeared to contain about 0.7 grams or 700 milligrams of mercury. Larger thermometers could contain substantially more. Scary, given that this link led me to another site that said a single gram of mercury was enough to pollute a twenty-acre lake. One site noted that advisories were commonly issued in states along the Great Lakes, warning of the high mercury content in fish.

I moved on to sites that provided information about mercury poisoning. They confirmed what my father had told me, that inhalation was a quick and effective way mercury could enter the body. I learned that it was a very bad idea to attempt to vacuum up a mercury spill, as it could break up the chemical and send it airborne, where a person might breathe it into their lungs. Yikes.

While I felt that I now knew quite a bit about the effects of mercury poisoning and the methods by which it could enter the body, I decided to learn more about sources of elemental mercury. If I learned about potential sources of mercury, maybe I could figure out how it had gotten into Joanna's system and help protect Macy and her baby. I also couldn't fight a niggling and growing feeling that maybe Joanna's death hadn't been accidental, that perhaps someone had slipped mercury to Joanna in one way or another.

My research provided some intriguing information. I learned that mercury is the only metal to remain in liquid form at room temperature, but that it easily vaporized. The fact that it could take several forms—solid, liquid, and vapor—made it especially difficult to manage. A pea-sized drop of liquid mercury would totally vaporize in just over a year. I also learned that mercury vapor is colorless and odorless, making it difficult to detect. What's more, mercury is heavier than water and should never be disposed of by pouring it down the drain, as it could become trapped in the pipes. One should never wash clothing that had come in contact with mercury, as doing so would release the mercury into the water and pose a health risk.

As for where mercury might be found, I discovered that it could come from any number of sources. Dental labs could be a source of mercury, as the metal comprised part of the silver amalgam used to fill cavities. Of course, just like thermometers had evolved to contain alcohol rather than mercury, fillings had evolved, too. These days a composite resin was more commonly used to fill teeth, and was preferred by many because it better matched the natural enamel and was less noticeable. Mercury was evidently an excellent conductor of electricity. The thermostats, sensors, switches, and relays in some HVAC systems contained mercury. My gut formed a hard ball when I read of an air-conditioner installer in Queens, New York, who had planted hundreds of beads of mercury in the ductwork in a family's home, after they'd made complaints. The family soon become very sick from a mysterious illness that was later identified as mercury poisoning. Horrifying!

But what gave me pause was a site that mentioned another potential source of mercury—switches used in cars manufactured before 2003, when mercury switches were phased out. There were even special handling procedures for mechanics to remove, store, and ship mercury switches for recycling of the metal.

You know who worked in auto salvage and might have access to old mercury switches?

Lane Hartzell, that's who.